How a Real Estate Investment Consultant Looks at a Rental
A listing tells you what a seller hopes to get. A real estate investment consultant starts from the other end: what the property is likely to earn after every realistic cost, and what that income is worth to you at your cost of borrowing. This guide walks through the numbers WealthTale.com calculates for every rental property we analyze, with a worked example you can copy into your own spreadsheet.
One point first. This is property analysis, not investment advice. Nobody can promise rent growth, appreciation or a return, and we don’t. What we can do is make every assumption visible so you can decide whether you believe it.
The Core Investment Metrics, With Formulas
Everything starts with net operating income (NOI): the rent you expect to collect, minus an allowance for vacancy and unpaid rent, minus operating expenses. NOI leaves out mortgage payments, depreciation and income taxes, which is what makes it useful for comparing properties bought in different ways.
- Cap rate = NOI ÷ purchase price. The property’s yield before financing. Useful for comparing similar properties in the same area. A cap rate far above nearby sales often signals a risk that the price already reflects.
- Cash-on-cash return = annual pre-tax cash flow ÷ total cash invested. Cash flow is NOI minus mortgage payments. Cash invested includes the down payment, closing costs and any upfront repairs.
- Gross rent multiplier (GRM) = price ÷ annual gross rent. A quick comparison that ignores expenses entirely, so treat it as a first filter only.
- Debt service coverage ratio (DSCR) = NOI ÷ annual mortgage payments. Below 1.0, the rent does not cover the loan. Many lenders look at this ratio on investment loans.
- The 1% rule asks whether monthly rent is at least 1% of the purchase price. It is a rough screen, not an answer. It ignores property taxes, insurance and HOA dues, which vary widely between cities, and few properties in high-cost markets pass it. Passing it doesn’t make a property a good investment, and failing it doesn’t rule one out.
A Worked Example (Hypothetical Numbers)
The figures below are invented for illustration. They are not a forecast for any market, and your own numbers will differ.
| Annual line item | Amount |
|---|---|
| Purchase price | $300,000 |
| Gross scheduled rent ($2,750 a month) | $33,000 |
| Less vacancy and credit loss (5%) | ($1,650) |
| Effective gross income | $31,350 |
| Property taxes | $4,500 |
| Insurance | $1,800 |
| Property management (8% of collected rent) | $2,508 |
| Repairs and maintenance | $1,650 |
| Capital reserve (roof, HVAC, appliances) | $1,650 |
| Other owner-paid costs (water, landscaping, accounting) | $900 |
| Net operating income | $18,342 |
Now assume a $75,000 down payment, $9,000 of closing costs and $6,000 of initial repairs, for $90,000 of cash invested, plus a $225,000, 30-year fixed loan at 6.5%. That payment works out to about $1,422 a month, or $17,066 a year.
- Cap rate: $18,342 ÷ $300,000 = 6.1%
- GRM: $300,000 ÷ $33,000 = 9.1
- 1% rule: $2,750 is 0.92% of the price, so the property fails the screen
- Annual cash flow: $18,342 minus $17,066 = $1,276, about $106 a month
- Cash-on-cash return: $1,276 ÷ $90,000 = 1.4%
- DSCR: $18,342 ÷ $17,066 = 1.07
What the example shows: the cap rate (6.1%) is lower than the loan’s yearly cost as a share of its balance (about 7.6%), so borrowing reduces the cash return. Bought with cash, the same property would return about 5.8% on $315,000 invested. The margin is also thin. At 10% vacancy instead of 5%, cash flow turns slightly negative, and at a 7.5% interest rate it is negative even at 5% vacancy. That is the kind of result we put in front of clients before they commit, not after.
Operating Expenses Buyers Underestimate
- Property taxes after the sale. Some jurisdictions reassess a property when it sells, so the seller’s current bill can understate yours. We look up the local assessment rules and tax rate.
- Insurance. A landlord policy is priced differently from a homeowner’s policy, and flood or wind coverage may be separate. Get quotes before you commit.
- HOA or condo dues and special assessments, plus association rules that limit or prohibit renting.
- Turnover costs: cleaning, paint, small repairs and leasing fees between tenants.
- Capital items with a known life: roof, HVAC, water heater and windows. We ask for their age and budget a reserve.
- Local compliance and admin: rental registration, licensing or inspection programs some cities require, plus accounting and legal fees.
Vacancy and Rent Assumptions
Never model 100% occupancy. We test at least two vacancy levels and assume at least one full turnover (the empty weeks plus the make-ready work) during your holding period. Rent estimates come from comparable rentals that actually leased recently, not from the highest asking rents online. Local rules matter too. Rent regulation, short-term rental restrictions and registration requirements vary by city and can change the numbers completely, so we flag anything that needs an attorney’s reading.
Financing an Investment Property
Lenders treat a rental differently from a home you will live in. Expect a larger down payment requirement and pricing that may differ from owner-occupied quotes. Freddie Mac’s weekly Primary Mortgage Market Survey is a useful benchmark for where rates are heading, but it is not an investment-property quote, so compare actual Loan Estimates for the property type and occupancy you intend.
Some lenders also offer loans underwritten mainly on the property’s rental income, often called DSCR loans. Compare their rates, fees and prepayment terms carefully. And state occupancy accurately on every loan application: describing a rental as your primary residence to get better terms is mortgage fraud. We can suggest several lenders to compare, and you choose who to work with.
Tax Questions to Take to Your CPA
We don’t give tax advice, but we make sure these items reach your CPA before you buy:
- Depreciation. IRS Publication 527 lists a 27.5-year recovery period for residential rental property under the general depreciation system. Land is not depreciable, so how the price is split between land and building matters.
- Repairs versus improvements. Which costs can be deducted in the year you pay them and which must be capitalized.
- Passive activity rules, which can limit how much of a rental loss you can deduct against other income.
- 1031 exchanges. Since 2018, like-kind exchange treatment applies only to real property held for business or investment, according to the IRS like-kind exchange guidance. The rules and deadlines are strict, and the tax is deferred, not eliminated.
- The eventual sale, including how depreciation taken during ownership affects the tax you owe.
Risks We Put in Writing
Every WealthTale.com analysis ends with a short risk list specific to the property. Typical items include rent that could fall rather than rise, a major repair arriving early, rising insurance and tax bills, rate resets on adjustable loans, eviction timelines that vary by state, and association or city rules that change after you buy. Liquidity belongs on the list too: selling a property takes time and costs money. Appreciation is possible but never certain, so we never make it the reason a deal works.
Where Our Analysis Fits
We analyze and advise. We don’t manage property, find tenants or represent you in the purchase: your licensed agent writes and negotiates the offer, and a title company or closing attorney handles the closing. Before you commit, a comparable-sales market analysis checks the price, and our buyer consulting covers inspections and offer strategy. Already own a rental and wondering whether to sell? Seller advisory compares selling with holding. Our disclaimer sets out the limits of what any analysis can tell you.
