Rental Property Cash Flow Analyzer

What is the difference between cap rate and cash-on-cash return?

These two metrics measure different things and are often confused.

Cap rate (capitalization rate) is financing-independent. It tells you what the property would return if you paid all cash — it's calculated as net operating income divided by purchase price. Because it ignores how you financed the property, cap rate is the standard metric for comparing properties against each other and against other asset classes like bonds.

Cash-on-cash return measures the actual return on your out-of-pocket cash investment. It divides your annual pre-tax cash flow (after mortgage payments) by the total cash you put in — down payment, closing costs, and upfront repairs. If you use leverage, cash-on-cash can be significantly higher or lower than the cap rate depending on whether your mortgage rate is above or below the cap rate. When borrowing costs exceed the cap rate, leverage hurts returns; when they're below it, leverage amplifies them.

A deal can have a strong cap rate (say 8%) but a weak cash-on-cash return (say 2%) if you borrowed at a high rate. Both numbers together give you a complete picture.

What is a good cap rate for a rental property?

It depends on the market, property type, and what you're comparing it to.

In high-cost coastal markets (New York, San Francisco, Los Angeles), cap rates for residential rental properties typically run 3–5%. In secondary and tertiary markets — the Midwest, the South, smaller metros — 6–9% is common. Class A properties in strong locations compress cap rates; older properties in less desirable submarkets offer higher ones.

Context matters just as much as the number. A 6% cap rate was attractive when 10-year Treasuries yielded 2%; the same 6% is much less compelling when risk-free bonds yield 4–5%, because the spread between the property yield and the risk-free rate narrows. This is why cap rates have risen since 2022 as interest rates climbed — property values had to adjust to maintain a reasonable risk premium.

As a rule of thumb: a cap rate higher than your mortgage rate means leverage is working in your favor. A cap rate below your mortgage rate means the property may not cash flow with typical financing, and you're relying more heavily on appreciation.

What does debt service coverage ratio (DSCR) mean, and why do lenders care about it?

The debt service coverage ratio (DSCR) is net operating income divided by annual debt service (mortgage payments). It answers the question: does the property generate enough rental income to cover its own mortgage?

• DSCR > 1.25 is typically the minimum most lenders require for investment property loans. It means the property earns 25% more than it needs to cover debt payments, providing a buffer for vacancies or unexpected expenses.
• DSCR between 1.0 and 1.25 means the property is barely self-sustaining. The lender and the investor are both taking on more risk.
• DSCR below 1.0 means operating income alone is insufficient to cover the mortgage. You'd need to subsidize the property from other income each month.

DSCR-based loans (sometimes called "no-doc" or "investor loans") are increasingly popular because lenders qualify the borrower based on the property's income rather than the investor's personal income. For these loan products, a DSCR of 1.25 is almost always the floor, and rates are more favorable at 1.35+.

What is the 1% rule for rental properties, and does it still apply?

The 1% rule is a quick screening heuristic: a rental property passes if its monthly gross rent equals at least 1% of the purchase price. A $200,000 property should rent for $2,000/month; a $400,000 property should rent for $4,000/month.

The logic is that at the 1% threshold, a property is likely to generate positive cash flow after typical expenses and a standard mortgage. Below 1%, you're generally relying on appreciation rather than income to justify the investment.

The rule still works as a filter, but it shouldn't be the final word. Its limitations:

• It ignores property taxes, insurance, and HOA costs, which vary dramatically by state and municipality. A property that hits 1% in a high-tax state may still underperform one at 0.85% in a low-tax state.
• It breaks down entirely in high-cost markets. Most properties in San Francisco or Manhattan will never approach 1% — investors there are buying for appreciation and equity, not cash flow.
• It doesn't account for the current interest rate environment. At 3.5% mortgage rates, the 1% rule often produced strong cash flow. At 7%+, even some 1.1% properties struggle to break even.

Use it as a 5-second first pass. If a deal clears 1%, run the full analysis. If it's well below 0.8%, it's probably not a cash-flow investment in the current rate environment.

What expenses should I include, and what does "net operating income" actually mean?

Net operating income (NOI) is the most important number in rental property analysis. It equals total rental income after vacancy, minus all operating expenses — but critically, it does not include mortgage payments. NOI is a property-level metric independent of how it's financed.

Operating expenses to include:

• Property taxes — often the largest fixed expense, typically 1–2% of assessed value per year
• Insurance — landlord/dwelling policy; usually $800–2,000/year for a single-family home
• Maintenance and repairs — budget 1% of property value annually as a reserve; older properties may need more
• Property management — typically 8–12% of collected rent if you use a manager; 0% if self-managing, though your time has value
• HOA fees — applies to condos, townhomes, and some single-family communities
• Utilities paid by owner — water, trash, or common-area electricity in some multi-unit setups
• Vacancy and credit loss — budget 5–10% of gross rent to account for turnover periods and occasional non-payment

Mortgage principal and interest are not operating expenses — they're financing costs that sit below the NOI line. A common mistake is to calculate NOI without a maintenance reserve or vacancy allowance, which produces an unrealistically optimistic picture of a property's performance.