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15-Rental 15-Year Mortgage Stagger Strategy Calculator

Model the long-game rental strategy: buy 15 rental properties on 15-year mortgages, one per year, then live on the tax-free cash from refinancing one paid-off property every year. Adjust the numbers for your market and see how much steady-state cash the portfolio can generate — and what rental cash flow looks like along the way.

Portfolio
Typical property (today's dollars)

Operating expenses cover vacancy, maintenance, property management, taxes, and insurance. A common rule of thumb is 35–50% of rent.

Refinance terms
Results
Annual cash in first refi year
$174,226
Year 16, in today's dollars
Tax-free refi proceeds$175,000
Rental cash flow (taxable)-$774

Refi proceeds aren't IRS-defined income — they're loan proceeds, which aren't taxed. Rental cash flow is taxable, but is often sheltered by depreciation for active investors.

Total cash invested
$937,500
First refi event
Year 16
Steady-state starts
Year 16
Portfolio equity at year 30
$2,301,075
Annual cash over time
Modeling assumptions to keep in mind
  • All numbers are in today's dollars; inflation and home appreciation are assumed to cancel out unless you change the advanced setting.
  • Refis are assumed to always be available at the rate, LTV, and term you set. In practice, lenders evaluate credit, income, and/or DSCR every time.
  • Rental cash flow is shown pre-tax. Depreciation often shelters most rental income for active investors, but rules vary — consult a CPA.
  • Refi proceeds are not taxed as income because loan proceeds are a liability, not income. Interest on the new loan is still owed and partially deductible.
  • This is an educational tool, not financial, tax, or investment advice.

About the 15-Rental Stagger Strategy

This calculator was inspired by a long-game rental strategy mentioned in David Greene's Pillars of Wealth. The core mechanic is to buy one rental property per year for 15 years, finance each with a 15-year mortgage (lower rate than a 30-year, more principal paid down faster), and let the portfolio's rents service the loans. After 15 years of payments on the first property, it's free and clear — and from then on, one more property finishes its mortgage every year. Each paid-off property can be refinanced with a cash-out loan, and because loan proceeds are not taxable income, that refi cash is yours to spend, tax-free.

This calculator lets you plug in your own numbers — purchase price, rent, down payment, interest rate, refi terms — and see the year-by-year picture. The headline output is the steady-state tax-free income you could draw from refis once the cycle is established. Underneath, the table shows portfolio cash flow, debt service, and refi events year by year.

Results are shown in today's dollars. The model assumes inflation and home appreciation roughly cancel out, so the numbers you see are what the strategy would feel like in current purchasing power. There's an advanced knob for real appreciation above inflation if you want to model a market that genuinely outpaces inflation. The model also assumes you can keep qualifying for refinances — a real-world risk worth thinking about, since lenders evaluate credit, income, and/or DSCR every time.

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Frequently Asked Questions

Is refinance cash really tax-free?

Yes — loan proceeds are not considered taxable income by the IRS, because a loan is a liability that must be repaid, not income. When you do a cash-out refinance and pull, say, $150,000 out of a paid-off rental, that $150,000 is not reported as income. You will pay interest on the new loan going forward, and you'll pay the principal back over time, but the cash itself is not taxed when you receive it. Always check with your CPA for your specific situation.

Why use 15-year mortgages instead of 30-year?

Two reasons. First, 15-year mortgage rates are typically 0.5%–0.75% lower than 30-year rates, so you save substantial interest. Second, principal pays down much faster, so each property reaches the payoff finish line in time to support the strategy's annual refi cadence. The trade-off is a higher monthly payment, which means the portfolio's early-year cash flow may be tighter — the more mature properties in the portfolio help carry the newer ones.

Is this strategy hard to pull off?

The biggest challenge is on the front end, not the back end. Finding rental properties that cash-flow — or even break even — on a 15-year mortgage is significantly harder than on a 30-year, because the higher monthly P&I payment leaves much less room for rent to cover it. You typically need a strong rent-to-price ratio (around 1% monthly or better) and disciplined operating costs to make the math work. Investors usually buy in lower-cost markets, hunt for off-market deals, or add value through renovations to push rents up. The model assumes you can keep finding properties that fit — in practice, sourcing one per year that pencils out can take real effort, and some years you may have to skip.

What happens if I can't qualify for a refinance later?

This is the biggest real-world risk of the strategy. Lenders evaluate every refinance based on credit, income (or DSCR — debt service coverage ratio — for investor loans), and overall debt load. If you've retired and have no W-2 income, or if the rental market has softened so the property doesn't cover the new payment by enough margin, you may not qualify. Mitigations: keep credit strong, build a cash reserve, use lenders that specialize in DSCR loans for investors, and don't pull the maximum LTV every time.

What if rents drop or vacancies rise?

The portfolio is designed to be self-supporting in aggregate — mature, low-debt properties subsidize newer, high-debt ones. If rents drop or vacancies spike across the board, the year-by-year table in the calculator will show negative portfolio cash flow, which means you'd need to cover the shortfall from the refi cash or other savings. Stress-test by lowering the rent or raising the operating expense percentage and see how much cushion remains.

Why are the numbers in today's dollars?

Modeling in today's dollars makes the output intuitive: $X tax-free per year means what $X buys today, not what it might buy 16 years from now. The calculator assumes that home appreciation and inflation grow at roughly the same pace, which has historically been a reasonable approximation. If you believe real estate will genuinely outpace inflation, there's an advanced setting for 'real appreciation above inflation' to model that upside.

Can I run this strategy with fewer than 15 properties?

Yes. The calculator lets you set any portfolio size from 1 to 30 properties and any cadence from 1 to 5 purchases per year. Fewer properties means a smaller refi pipeline, which means less tax-free income per year at steady state. More properties, or buying multiple per year, accelerates the cycle. The math is the same — the calculator just scales the inputs.

Can I model properties that differ from each other?

Yes. Real portfolios rarely have 15 identical properties — prices, rents, and rates vary deal by deal. Open the Advanced settings panel and toggle on 'Customize each property individually.' A table appears with one row per property where you can override the purchase price, down payment, mortgage rate, monthly rent, or operating-expense percentage for any specific property. Leave a cell blank to fall back to the typical-property defaults above. This is useful for modeling a mix of higher-priced and lower-priced rentals, or properties acquired at different rate environments.

What happens after a refinanced property pays off again?

The cycle continues: each refi loan in this model has its own term (15 or 30 years), and when that refi pays off, the property can be refinanced again. The calculator simulates this perpetual cycle, so a 30-year projection on a 15-year refi term will show a second refi event on the first property around year 30.

Is the cash flow from the rentals also tax-free?

No. Rental cash flow is generally taxable, though depreciation often shelters most or all of it for active investors. The strategy's appeal is the layer on top: even if your rental cash flow is modest and fully taxed, the annual refi proceeds add a meaningful, tax-free income stream that the IRS does not treat as income at all. This calculator shows the refi cash separately from rental cash flow so you can see both clearly.

Is this financial advice?

No. This calculator is an educational tool that models a long-discussed real estate strategy. It does not account for every real-world variable — capital expenditures, property management quirks, regulatory changes, loan qualification hurdles, market cycles — and it is not personalized advice. Talk to a licensed CPA, financial advisor, and mortgage broker before committing to any strategy of this scale.

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