Net Operating Income is the metric that determines property value. A $100,000 error in NOI, at a 6% cap rate, is $1.67 million in lost property value. The errors that destroy NOI are not dramatic. They are small, recurring, and invisible until they accumulate.
This article identifies the five most common accounting errors in commercial real estate and shows the NOI impact of each.
Error 1: Missed Reimbursements
What it is: A recoverable expense is paid by the property but never billed to the tenant.
How it happens: The invoice is coded to the wrong account. The expense is not flagged as recoverable. The tenant billing system is not updated. The reconciliation is done by hand and the item is skipped.
NOI impact: Direct reduction in revenue. A $10,000 recoverable expense that is not billed reduces NOI by $10,000.
Example: A $8,000 HVAC repair is coded to "Repairs and Maintenance" instead of "Recoverable Repairs." The lease allows recovery. The expense is never billed. The property absorbs $8,000 that should have been passed through.
Error 2: Incorrect Expense Allocations
What it is: An expense is allocated to the wrong pool, the wrong tenant, or the wrong account.
How it happens: The pro-rata percentage is outdated. The expense is coded to the wrong GL account. The CAM pool includes a non-recoverable expense. The tax pool excludes a recoverable tax increase.
NOI impact: Overstatement of expenses or understatement of recoveries. Both reduce NOI.
Example: A $15,000 roof repair is allocated to the CAM pool. The lease excludes roof repairs as capital expenses. The CAM pool is overstated by $15,000. Tenants are overbilled. The property faces a refund claim.
Prevention: Expense allocations are validated against lease terms automatically. The system checks every expense against the recovery rules before it enters the pool.
Error 3: Missed Escalations
What it is: A scheduled rent increase is not applied.
How it happens: The escalation date is not tracked. The amendment changing the rate is not entered. The spreadsheet formula references the wrong cell. The person who tracked escalations left.
NOI impact: Compounding revenue loss. A missed 3% escalation on $50,000 rent is $1,500 in year one and $15,456 over five years.
Example: A 5-year lease at $40,000 with 3% annual escalation. The escalation is missed in year 2. The tenant pays $40,000 instead of $41,200. The correct rent in year 5 is $45,010. The billed rent is $40,000. The 5-year loss is $12,350.
Prevention: Escalation schedules are extracted from the lease and applied automatically. Amendments update the schedule. The system flags any variance between billed and calculated rent.
Error 4: Duplicate Expenses
What it is: The same expense is recorded twice.
How it happens: The invoice is entered manually and then imported electronically. A credit memo is not applied. The same invoice is received from two different email addresses. A vendor resubmits an invoice and it is paid twice.
NOI impact: Overstatement of expenses. Direct reduction in NOI.
Example: A $6,500 landscaping invoice is entered when received by email and again when imported from the vendor portal. The expense is recorded twice. NOI is reduced by $6,500. The error is not found until the annual audit.
Prevention: Duplicate detection runs automatically. The system flags invoices with matching vendor, amount, and date. Credits are matched to original invoices.
Error 5: Inaccurate Accruals
What it is: An expense is accrued at the wrong amount, in the wrong period, or not reversed when the actual invoice arrives.
How it happens: The accrual is estimated and never trued up. The invoice arrives in a different period and the accrual is not reversed. The accrual is based on last year's amount and the actual cost changed.
NOI impact: Timing differences that distort monthly and annual NOI.
Example: A $12,000 utility accrual is recorded in December. The actual invoice is $14,000 and arrives in January. The December accrual is not adjusted. December NOI is overstated by $2,000. January NOI is understated by $14,000. The annual NOI is correct, but the monthly reports are wrong.
The Cumulative NOI Impact
| Error | Frequency | Average Amount | Annual NOI Impact (50-property portfolio) |
|---|---|---|---|
| Missed reimbursements | 2-5% of recoverable expenses | $5,000-$15,000 | $25,000-$75,000 |
| Incorrect allocations | 3-8% of pool activity | $3,000-$10,000 | $15,000-$50,000 |
| Missed escalations | 2-5% of escalation events | $1,500-$5,000 | $10,000-$40,000 |
| Duplicate expenses | 1-2% of invoice volume | $2,000-$8,000 | $5,000-$20,000 |
| Inaccurate accruals | 5-10% of accruals | $1,000-$5,000 | $10,000-$30,000 |
| Total | $65,000-$215,000 |
A 50-property portfolio loses $65,000 to $215,000 per year to these five errors. At a 6% cap rate, that is $1.1 million to $3.6 million in lost property value.
The Komod.ai Approach
Komod.ai addresses all five errors through a single control layer:
- Incorrect allocations: Expense pools are validated against lease rules. Pro-rata percentages are current. Caps are enforced.
- Missed escalations: Schedules are extracted from leases and applied on schedule. Variances are flagged before billing.
- Duplicate expenses: Duplicate detection runs on every transaction. Credits are matched automatically.
The result is not error detection after the fact. It is error prevention at the point of entry.
Conclusion
The five errors that destroy NOI are not exotic. They are the routine failures of manual accounting: missed reimbursements, incorrect allocations, missed escalations, duplicate expenses, and inaccurate accruals. Each is small. Together they are material.
The fix is not more review. It is a system that prevents the error from entering the books.
Komod.ai is an AI-native operating layer for the commercial real estate back office. The platform reads leases, invoices, and bank activity; performs deterministic calculations; and stages completed work for human approval. Nothing posts without you.