Dental DSO Overhead Reduction: A CAM Audit Playbook for Multi-Location Portfolios
Dental service organizations have spent a decade tuning their overhead. They fixed supply chains. They centralized billing. They cut dental supply costs through group buyers like Benco Dental and Schein. The playbook for cutting practice overhead is now standard. But one cost is not in it. That cost is CAM overcharges. CAM is common area maintenance, the shared building costs a landlord bills to tenants. An overcharge is paying more than the NNN lease allows, at one location after another. NNN means the tenant pays its share of taxes, insurance, and maintenance. This cost belongs in the playbook.
I built CAMAudit because these errors follow patterns. They are not random. I tested reconciliation samples from published audit cases through CAMAudit. The same error types show up in dental and medical leases at a steady rate. Pro-rata share math that inflates the tenant's share. Management fees charged on a base that includes banned costs. Big capital costs relabeled as operating costs to dodge amortization. Amortization spreads a large cost over the years the asset lasts. This playbook covers each pattern. It also shows how DSO advisory firms can deliver forensic cost review as a standard part of the engagement. A pro-rata share is the slice of shared costs a tenant pays.
Dental DSO CAM Overcharge: An annual billing error in a dental practice's common area maintenance reconciliation under a NNN or modified gross lease. Overcharges occur when the landlord applies a management fee, pro-rata share calculation, or expense classification that deviates from the lease terms. Because DSO portfolio leases are managed at the individual location level rather than centrally, overcharges at acquired or de novo locations often compound across multiple reconciliation periods before detection.
Why DSO leases go unchecked
The DSO model creates a blind spot. DSOs are great at centralizing what scales. That means buying, HR, credentialing, billing, and marketing. The lease does not scale the same way. Each location has its own lease, its own landlord, and its own bill cycle. When a DSO buys a new or used practice from a solo dentist, the lease comes with the building. It does not come with the DSO's standard process.
The result is a set of leases managed one at a time and billed one at a time. No one checks whether the yearly bills match the lease terms. The CAM bill arrives from the property manager in February or March. It flows into the occupancy line on the location P&L. It gets paid with no review. At the DSO level, the financial statement shows one occupancy cost percentage. It does not show the billing accuracy of 20 separate CAM statements.
MGMA practice data and DSO benchmarks like Levin Group agree on one point. Occupancy is a top-five overhead driver for dental practices. The occupancy line is easy to see. But the CAM piece of that line changes every year on the landlord's own accounting. No one checks it as hard as they check supply costs or staffing.
For a DSO advisory firm working on overhead, this gap is a chance to recover money. It exists at every NNN location in the portfolio.
The three most common overcharge patterns
Pro-rata share denominator errors
The pro-rata share is the slice of building CAM costs each tenant pays. You find it by dividing the tenant's square footage by the building's leasable area. That bottom number is the denominator. The lease defines it. What the landlord uses often differs from what the lease requires.
Anchor tenant left out with no lease basis. Some MOBs have an anchor like a hospital system or a large orthopedic group. The landlord sometimes drops the anchor's square footage from the denominator. If the lease does not allow that, the denominator shrinks. Every other tenant's share goes up. Take a dental practice with 2,000 square feet in a 40,000 SF building with a 10,000 SF anchor. Dropping the anchor raises the practice's share from 5% to 6.7%. That is a 34% overcharge.
Vacant space left out. Some leases require the landlord to count vacant space in the denominator. That spreads the empty-space risk across all tenants. If the landlord drops vacant suites, the denominator shrinks. Every occupied tenant pays a higher share. IREM standards cover how to treat vacancy in CAM math. But the lease term controls, not industry norms.
GLA versus leasable area. Gross leasable area and the lease's leasable area are not always the same number. Common areas, storage, and mechanical rooms sometimes count in GLA but not in the lease definition. Using GLA when the lease defines something smaller overcharges every tenant in the building.
Use the pro-rata share error guide to model these errors on your clients' sites before you route documents through CAMAudit.
Management fee overcharges
Management fees in NNN leases are usually a percentage of collected rent or of total CAM costs. The lease sets the base and the percentage cap. Overcharges come in two forms.
Fee charged on a base that is too big. When the fee is a percentage of total CAM costs, the meaning of "total CAM costs" matters a lot. Many leases drop capital costs, tenant improvement costs, and some admin costs from the fee base. If the landlord adds those back into the base, the fee goes above what the lease allows.
Take a dental practice with $120,000 in yearly CAM charges. Say $30,000 of that is capital costs the lease excludes from the fee base. A 5% fee on the full $120,000 is $6,000. The correct fee, on the $90,000 base, is $4,500. The overcharge is $1,500 per year. Over a five-year lease that is $7,500, before any year-over-year CAM increase.
Fee over cap. Some leases set a cap. Check the rate and base in the bill. Check the lease. Check records.
The partner-led CAM review helps advisors review the CAM audit workflow before a deeper engagement.
"I built CAMAudit so a DSO can check management fee math and pro-rata share denominators across its own leases. A portfolio count does not prove that any file has an error." - Angel Campa, Founder of CAMAudit
Capital cost misclassification
Capital costs extend a building part's life or add new capacity. Under GAAP, IRS Publication 535, and almost every standard lease, capital costs are handled one of two ways. They are kept out of the CAM pool. Or they are amortized over the asset's life, and only the yearly amortization amount passes to tenants.
Dental sites in medical office buildings hit a sharp version of this. MOBs have complex HVAC systems. Autoclaves, operatory suites, and sterilization areas need special ventilation beyond a normal office. When those systems wear out, the landlord replaces them. That replacement is a capital cost. Say the landlord bills the full replacement cost in one year instead of amortizing it over the asset's 15 to 20 year life. Then every tenant in the building eats too large a charge.
The ASHRAE Guideline 14 standard and the IREM rules both draw a clear line between capital and operating costs. The lease terms control what the landlord can pass through. If the lease excludes capital costs or requires amortization, a one-year passthrough of a rooftop unit is an overcharge under the lease. It is not just an accounting dispute.
Pre-acquisition due diligence: the best use case for DSOs
The DSO buying market is more competitive now. Prices for practices in good markets have risen. Buyers include private-equity DSO platforms, regional groups, and solo dentists going DSO. In this market, every cost you catch in diligence is margin from day one of ownership.
A CAM audit in pre-acquisition due diligence gives three clear benefits.
Overcharge numbers as a price lever. Say the target practice has paid a $7,000 yearly management fee overcharge for three years. The total overpayment is $21,000, plus the ongoing overpayment at the new rate. That $21,000 is a documented liability at the time of the deal. A DSO advisory firm that finds it in diligence can negotiate. It can push for a lower price, an escrow holdback, or a warranty that names the exposure.
Dispute window check. Leases have audit rights clauses. They set the window to dispute a bill. That window is usually one to three years from the bill date. After the close, the DSO inherits whatever window is left on prior bills. A CAM audit in diligence shows which prior periods are still inside the window. It shows whether the findings are big enough to pursue before the window closes. After the deadline, recovery gets much harder, so review it with counsel.
Lease quality check for the go-forward portfolio. Beyond prior-period recovery, the diligence audit reviews the lease's protective terms. Does it have a CAM cap? Does it have a controllable expense cap that limits yearly rises on certain costs? Does it have a gross-up clause, and is it built right? A gross-up clause adjusts shared costs as if the building were full. These terms set the DSO's cost exposure for the rest of the lease. A lease with no CAM cap in a rising-cost market is a long-term risk. It belongs in the deal model.
Use the partner-led CAM review to review the workflow before you commit to a full diligence audit.
How to run CAM audits at scale
A DSO advisory firm may manage 10 to 50 locations. The workflow has to repeat and document well. This sequence works across portfolio sizes.
Phase 1: Portfolio review (one to two weeks)
Rank sites by expected exposure. A 3,500 SF practice in a 12-year-old MOB with a high-fee manager ranks higher than a 1,500 SF new site on a fresh lease with strong protective terms. The partner-led CAM review outlines the CAM audit workflow. You do not have to run a full audit on every site.
Phase 2: Upload and scan (one to two days per batch)
Route the CAM bills and lease sections through CAMAudit. The platform checks the CAM detection rules and returns findings for partner review. Processing time depends on file quality, document complexity, and batch size. For a 20-location portfolio, stagger the uploads in batches so the partner can review one batch before the next finishes.
Phase 3: Partner review and ranking (two to four hours per site)
Before you deliver findings, the advisory team reviews each one. The review catches unclear lease language. It flags findings with missing documents. It ranks the disputes worth pursuing by dollar amount and strength. Not every finding is equally usable. A management fee overcharge with a clear cap is easier to act on than a pro-rata error where the lease language is fuzzy.
Phase 4: Portfolio report delivery
Deliver one combined report. It shows total exposure across all sites, ranked by recovery chance. For a DSO client, the portfolio view beats single-site reports. It drives portfolio decisions. Which sites to pursue. Which leases to renegotiate at renewal. Which findings to put in the deal model.
White-label CAM audit service for DSO advisory firms
Some DSO advisory firms want to sell the work under their brand. The CAMAudit white-label service helps them do that. It is built for firms with multi-site clients.
Audit packs. You buy audit credits sized to your portfolio. One credit equals one location for one reconciliation year. A firm advising a 25-location portfolio on a yearly cycle can start with a smaller pack, then add audit credits when volume grows. Catch-up audits on newly bought portfolios may need extra credits in year one.
Your brand throughout. Every client-facing piece carries your firm's brand. That covers the client portal, the findings reports, the dispute letter drafts, and all system messages. The DSO client works with your firm, not the platform. This fits firms that want to own the cost advisory relationship for the long term.
Dispute letter draft generation. For each real finding, CAMAudit writes a dispute letter draft. It cites the lease clause, states the overcharge, and asks for a fix. Your firm and the DSO's counsel review the package before the client picks a next step. You choose the tone: collaborative, neutral, or firm.
Lease renewal advisory. Audit findings can support a lease renewal. Show the billing history. Propose clear caps, exclusions, and pro-rata terms. This can turn one audit into ongoing client work.
Full program details are at /partners/white-label. For firms still evaluating, the RCM consultant service line guide covers the same workflow for healthcare-adjacent advisors.
For more DSO context, see ophthalmology practice rollup CAM due diligence and healthcare overhead reduction.
Frequently Asked Questions
Why do dental DSOs systematically miss CAM overcharges in their practice portfolios?
DSOs consolidate clinical operations, supply chains, and billing under centralized management, but commercial leases typically remain decentralized: each practice location carries its own lease, managed by the prior owner or a regional property manager. CAM reconciliations arrive annually from individual landlords and flow into occupancy cost line items on the P&L without systematic forensic review. The charges look fixed. They are not.
What is a pro-rata share error in a dental office NNN lease?
A pro-rata share error occurs when the landlord uses the wrong denominator to calculate the dental practice's share of building-wide CAM expenses. Common errors include using total gross leasable area (GLA) instead of the leasable area defined in the lease, excluding vacant space from the denominator when the lease requires inclusion, or failing to exclude anchor tenant space as specified. Each error inflates the tenant's share and produces an overcharge compounding across every year the error persists.
How large is a typical CAM overcharge for a dental office in a medical office building?
Recovery amounts depend on the lease structure, the property, and the error type. Dental practices in MOBs typically pay between $8 and $22 per square foot annually in CAM charges, according to BOMA operating expense benchmarks for medical office properties. A management fee error or pro-rata share miscalculation on a 2,000 square foot practice can produce annual overcharges of $3,000 to $10,000 or more. Multi-year lookback provisions in most commercial leases allow recovery from the prior one to three years.
At what stage of a DSO acquisition should a CAM audit be conducted?
A CAM audit should be part of pre-acquisition due diligence, not post-close remediation. Once the acquisition closes, the DSO inherits the lease and its payment history. Any overcharges paid before the close may be harder to recover depending on lease assignment and audit rights provisions. A CAM audit during due diligence quantifies occupancy cost exposure, provides leverage for lease renegotiation, and identifies whether prior reconciliation periods are still within the dispute window.
How does the CAMAudit white-label CAM audit service work for DSO advisory firms?
Under the white-label CAM audit service, the DSO advisory firm delivers all findings reports, dispute letter drafts, and client portal access under its own branding. The dental DSO client sees the advisory firm's logo and contact information throughout the engagement. The underlying forensic analysis uses CAMAudit's CAM detection rules. Yearly audit packs are sized to match the DSO's portfolio volume, and unused audit credits stay available after purchase.
What documents does a DSO advisor need to run a CAM audit for a practice location?
Two documents are required: the annual CAM reconciliation statement from the landlord (which arrives between January and April for the prior calendar year) and the relevant sections of the commercial lease, including the CAM expense pool definition, pro-rata share methodology, management fee provisions, any exclusions, gross-up language, and the audit rights clause. For acquired practices, these documents may be in the prior owner's files or held by the property management company.
Can CAM audit findings be used in DSO lease renewal negotiations?
Yes, and this is one of the highest-value applications. A documented audit finding showing the landlord has been overcharging for management fees or applying an incorrect pro-rata share formula is direct leverage in a renewal negotiation. It gives the DSO advisory team a factual basis for demanding corrected billing going forward and for negotiating favorable cap language, base year adjustments, or exclusion lists into the renewed lease.
Sources
- BOMA International. "Experience Exchange Report: Medical Office Buildings." Building Owners and Managers Association. https://www.boma.org/
- IREM. "Income/Expense Analysis: Office Buildings." Institute of Real Estate Management. https://www.irem.org/
- Tango Analytics. "Lease Administration and CAM Reconciliation Accuracy Report." https://www.tangoanalytics.com/
- MGMA. "MGMA DataDive: Dental Practice Overhead Benchmarks." Medical Group Management Association. https://www.mgma.com/data
- Levin Group. "Annual DSO Performance Report." Dental Group Practice Advisory. https://www.levingroup.com/
- IRS. "Publication 535: Business Expenses." Internal Revenue Service. https://www.irs.gov/publications/p535
- FASB. "ASC 842: Leases." Financial Accounting Standards Board. https://www.fasb.org/
- ASHRAE. "Guideline 14: Measurement of Energy, Demand, and Water Savings." American Society of Heating, Refrigerating and Air-Conditioning Engineers. https://www.ashrae.org/
Disclaimer: This article provides general guidance for DSO advisory firms evaluating CAM audit services as a due diligence and portfolio advisory capability. It is not legal, accounting, or tax advice. Recovery amounts depend on lease terms, property type, and error type. CAM expense benchmarks are derived from BOMA Experience Exchange Report data and are provided for illustrative context only. Consult qualified commercial real estate counsel for advice specific to your clients' lease situations and acquisition transactions.