The Core Rules of Thumb

Rental property rules of thumb for 2025

RuleThresholdWhat It Screens For
1% RuleMonthly rent ≥ 1% of purchase priceCash flow positive potential (challenged at 7% rates)
50% RuleOperating expenses ≈ 50% of gross rentRealistic expense estimate
Gross Rent MultiplierGRM ≤ 12 (GRM = Price ÷ Annual Rent)Reasonable price relative to income
Cap Rate minimumCap rate ≥ 6% in 2025 for positive cash flowIncome yield benchmark
DSCR minimumDSCR ≥ 1.25 (NOI ÷ Debt Service)Loan qualifying and safety
70% Rule (BRRRR)Buy at ≤ 70% of ARV − repair costsValue-add deal screen
⚠️The 1% Rule in 2025

The 1% Rule (monthly rent ≥ 1% of purchase price) was a reliable cash flow indicator when mortgage rates were 3–4%. At 7% rates: 1% Rule properties barely break even or produce slight negative cash flow. The rule still works as an initial screen but no longer guarantees positive cash flow as it did in 2020. In 2025: target 1.1–1.3% to achieve meaningful positive cash flow at current rates.

Rules of Thumb for BRRRR Investors

BRRRR-specific rules of thumb

RuleFormulaTarget
Maximum purchase price70% of ARV − repair costsLeaves room for refi + profit
Repair contingencyContractor estimate × 1.25Budget for unknowns
Refinance LTV target75% of ARVLeaves 25% equity in property
Cash recycled minimumRecover 90%+ of invested cashTrue BRRRR achievement

The Break-Even Rent Calculation

Calculate the minimum rent needed to break even: Total monthly expenses (mortgage + taxes + insurance + management + maintenance + CapEx reserve + vacancy allowance). On a $250,000 property with 20% down at 7%: mortgage $1,329 + expenses $600 = $1,929/month needed to break even. If market rent is $1,650: this deal produces −$279/month. If market rent is $2,100: positive $171/month.

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