How to Evaluate Operating Expenses Before Buying a Twin Cities Apartment Building
When evaluating an apartment building in Minneapolis, St. Paul, or the surrounding Twin Cities suburbs, rental income is only half the story.
A property may generate substantial monthly rent, but the amount remaining after operating expenses can vary dramatically from one building to another.
Two apartment buildings with similar purchase prices and rental income may produce very different investment returns because of differences in property taxes, insurance, utilities, maintenance, and management costs.
For investors considering a 5–20-unit apartment building, understanding operating expenses is essential to determining both the property’s value and its potential cash flow.
Here’s what buyers should examine before making an investment decision.
1. Why Operating Expenses Matter
Operating expenses directly affect a property’s net operating income (NOI).
The basic formula is:
Net Operating Income = Effective Gross Income − Operating Expenses
Effective gross income represents rental and other property income after accounting for vacancy and collection losses.
NOI represents the income remaining after ordinary operating expenses but before mortgage payments, income taxes, depreciation, and major capital expenditures.
Investors use NOI to evaluate property performance, estimate value, and determine how much income is available to support financing.
For example, consider two hypothetical eight-unit apartment buildings:
| Annual financial performance | Building A | Building B |
|---|---|---|
| Effective gross income | $120,000 | $120,000 |
| Operating expenses | $42,000 | $54,000 |
| Net operating income | $78,000 | $66,000 |
Both buildings generate the same effective gross income.
However, Building A produces $12,000 more annual NOI.
At a hypothetical 6% capitalization rate, that difference could represent approximately $200,000 in indicated property value, assuming the same cap rate is appropriate for both buildings.
This illustrates why investors should examine operating expenses just as carefully as rental income.
2. Property Taxes: One of the Largest Expenses
Property taxes are often among the largest operating expenses for Twin Cities apartment buildings.
Buyers should review the property’s current tax statement, assessed value, classification, and applicable tax information.
However, the seller’s current property taxes may not accurately represent what the buyer will pay in the future.
Minnesota property taxes depend on factors including assessed market value, property classification, local tax levies, and applicable tax rules.
A sale does not necessarily trigger an immediate reassessment to the purchase price, but future assessments and tax obligations can change.
Investors should evaluate the potential for higher property taxes rather than assuming the current amount will remain unchanged.
When analyzing a property, I recommend reviewing several years of tax history when available.
3. Insurance Costs Can Change Significantly
Insurance is another expense that deserves careful attention.
Apartment building insurance costs can vary based on:
- Building age and construction type
- Roof age and condition
- Claims history
- Property location
- Coverage limits and deductibles
- Replacement cost estimates
- Insurer underwriting requirements
A seller’s existing insurance premium may not be available to a new owner.
Before purchasing, buyers should obtain their own insurance quotations based on the property’s actual characteristics and intended use.
This is particularly important for older buildings with aging roofs or other deferred maintenance.
An unexpectedly high insurance premium can materially reduce projected cash flow.
4. Utilities: Who Pays for What?
Utility expenses can vary dramatically between apartment buildings.
Some properties have separately metered gas and electricity, with tenants paying most of their own utility costs.
Others have central heating systems or shared utility arrangements that require the owner to pay substantial expenses.
Common owner-paid utilities include:
- Natural gas or heating fuel
- Electricity for common areas
- Water and sewer
- Trash collection
- Exterior lighting
- Common-area heating
For example, an older eight-unit building with owner-paid heat may have a significantly different expense structure than a similar building with individually metered furnaces.
Buyers should request actual utility bills whenever possible rather than relying solely on estimates.
In Minnesota, heating expenses can be particularly significant during the winter months.
A building’s utility configuration can have a meaningful effect on its NOI and market value.
5. Repairs and Maintenance: Look Beyond the Seller’s Numbers
One of the most common mistakes investors make is assuming that the seller’s historical repair expenses represent what the buyer should expect going forward.
Some owners perform much of their own maintenance.
Others defer repairs or have unusually low expenses during a particular year.
A property might show only $3,000 in annual repairs, but that doesn’t necessarily mean $3,000 is a realistic long-term maintenance budget.
Investors should consider:
- Building age
- Condition of mechanical systems
- Plumbing and electrical infrastructure
- Appliance replacement history
- Tenant turnover
- Exterior maintenance needs
- Past repair records
A prudent analysis should include a reasonable allowance for ongoing maintenance, even when historical expenses have been unusually low.
The appropriate amount varies by property.
6. Property Management Expenses
Some smaller apartment building owners manage their properties personally.
As a result, their financial statements may show little or no property management expense.
However, an investor evaluating the property should consider what professional management would cost.
Even buyers who intend to manage the property themselves should recognize that management requires time and effort.
A management allowance helps create a more realistic comparison between properties.
Management costs vary depending on the number of units, services provided, property location, and the management agreement.
Additional charges may apply for leasing, tenant placement, maintenance coordination, or other services.
A property should not automatically appear more profitable simply because the current owner performs management duties without recording an expense.
7. Vacancy and Collection Losses
A fully occupied apartment building may look attractive on paper.
However, investors should not assume every unit will remain occupied and every tenant will pay rent on time indefinitely.
A vacancy and collection allowance accounts for potential lost rental income.
For example, an apartment building with $150,000 in annual scheduled rent and a hypothetical 5% vacancy and collection allowance would have:
$150,000 × 5% = $7,500
That reduces projected rental income to $142,500 before considering other income.
Actual vacancy assumptions should reflect the property’s operating history, tenant turnover, unit mix, and local rental market.
Vacancy and collection losses are generally deductions from potential gross income rather than operating expenses, but they are essential to calculating realistic effective gross income and NOI.
8. Capital Expenditures Are Different From Operating Expenses
A particularly important distinction is the difference between ordinary maintenance and major capital expenditures.
Routine repairs are generally included in operating expenses.
Major improvements or replacements are typically treated separately when calculating NOI.
Examples of capital expenditures may include:
- Replacing an entire roof
- Installing a new boiler
- Replacing major plumbing systems
- Significant parking lot reconstruction
- Major building renovations
Although capital expenditures are generally excluded from NOI, they are real costs that investors must consider.
For example, a ten-unit apartment building might generate $80,000 in annual NOI but require a $100,000 roof replacement in the near future.
That upcoming expense can materially affect the amount a buyer is willing to pay.
Buyers should evaluate both current operating performance and anticipated capital improvement needs.
9. Calculating an Apartment Building’s Expense Ratio
An operating expense ratio can provide a useful starting point for comparing properties.
The formula is:
Operating Expense Ratio = Operating Expenses ÷ Effective Gross Income
Suppose a twelve-unit apartment building has:
- Effective gross income: $180,000
- Operating expenses: $72,000
- Net operating income: $108,000
The operating expense ratio would be:
$72,000 ÷ $180,000 = 40%
That means 40 cents of every dollar of effective gross income is used for operating expenses.
However, expense ratios vary significantly depending on the property’s age, utility arrangements, tax burden, management structure, and condition.
A lower expense ratio is not automatically better if it reflects deferred maintenance or missing expenses.
Similarly, a higher expense ratio may be reasonable for a building with owner-paid utilities or more extensive services.
Expense ratios are useful comparison tools, not substitutes for detailed financial analysis.
10. Verify the Numbers Before Purchasing
Before purchasing an apartment building, buyers should review the property’s financial information carefully.
Important documents may include:
- Current rent roll and leases
- Historical operating statements
- Property tax records
- Insurance information and quotations
- Utility bills
- Repair and maintenance history
- Service contracts
- Capital improvement records
- Municipal licensing and inspection information
Whenever possible, buyers should compare seller-provided information with supporting documentation.
A careful analysis may also involve adjusting reported expenses to reflect realistic future operating costs.
For example, a buyer may need to account for professional management, higher insurance premiums, or anticipated property tax changes.
The objective is to determine what the property is likely to earn under reasonable ownership assumptions—not simply accept the most optimistic figures presented.
11. How Operating Expenses Affect the Price You Should Pay
Ultimately, the purchase price must make sense relative to the property’s expected income, operating costs, financing requirements, and condition.
Suppose an apartment building is advertised with annual NOI of $100,000.
After reviewing the expenses, a buyer determines that realistic NOI is closer to $85,000.
At a hypothetical 6% cap rate:
Seller’s advertised NOI:
$100,000 ÷ 0.06 = approximately $1,666,667
Buyer’s adjusted NOI:
$85,000 ÷ 0.06 = approximately $1,416,667
That’s a difference of approximately $250,000 in indicated value.
This does not mean the property’s market value automatically changes by that amount.
Actual value also depends on comparable sales, investor demand, financing, property condition, and the appropriate market capitalization rate.
Nevertheless, the example illustrates why careful expense analysis is so important.
A buyer who overlooks operating expenses may substantially overestimate a property’s financial performance.
Buying or Selling a Twin Cities Apartment Building?
Whether you’re evaluating your first small apartment building or considering selling a property you’ve owned for many years, accurate operating expense analysis is essential.
At Inside Track Realty, LLC, we specialize in Twin Cities investment properties, including duplexes, fourplexes, and small apartment buildings.
Our real estate experience dates back to 1993, with an investment-property focus since 2003.
We help buyers and sellers evaluate rental income, operating expenses, property condition, comparable sales, and financing considerations.
Interested in buying a Twin Cities investment property?
Visit our Find Investment Properties page on insidetrackrealty.com.
Considering selling—or wondering what your apartment building may be worth?
Request an Investment Property Valuation:
Call Inside Track Realty: 612-270-4141
Disclaimer: All financial examples are hypothetical and provided for educational purposes. Actual income, operating expenses, capitalization rates, property values, and investment returns vary by property and market conditions.