Rental property underwriting

Run the numbers before you make the offer.

Test the rent, loan, operating costs, reserves, and downside case. Save the deal only if you want to compare it with the rest of your portfolio.

  • Cash flow, cap rate, CoC, and DSCR
  • Conservative, base, and optimistic cases
  • Break-even occupancy and reserve target
  • Five- and ten-year equity outlook

No signup or bank connection required.

Base case

123 Main Street

Purchase price

$250,000

Monthly cash flow

$352

Cash-on-cash

6.51%

Cap rate

8.08%

DSCR

1.26

Gross monthly rent
$2,400
Operating expenses
−$788
Mortgage payment
−$1,260
Cash required
$65,000
Base case clears the reserve target and remains cash-flow positive at 82.85% occupancy.

One model, two views

Carry a reviewed deal into your portfolio.

The rent, loan, expenses, and growth assumptions from the deal analyzer become the starting point for a saved property. No second set of inputs and no hidden conversion between tools.

Review the calculator
01

Enter the deal

Purchase terms, financing, rent, expenses, reserves, and growth assumptions.

02

Stress-test it

See returns, break-even occupancy, warnings, and three sensitivity cases.

03

Keep planning

Create a free account and continue the reviewed property and mortgage.

Why use a portfolio model

Keep comparisons consistent.

Spreadsheets break quietly

A changed formula or stale loan balance can alter a comparison without leaving a clear trail.

Single-property calculators stop too early

They can price one deal, but not the effect of that deal on household cash, debt, or another property.

Each option gets different assumptions

Buying, selling, and paying down debt should be tested against the same timeline and market assumptions.

Workflow

Three steps, with the assumptions left in view.

1

Enter your current portfolio

Your rentals with rent, taxes, vacancy, and repairs. Your mortgages with rates and payments. Your cash, stocks, income, expenses, and goal.

2

Schedule portfolio transactions

Set the timing for a sale, refinance, debt payoff, or purchase. Cash-triggered purchases occur only when the required funds are available.

3

Compare the results

Review net worth, cash flow, debt, and time to goal. The ranking rules and assumptions remain visible.

Portfolio workspace

The records and comparisons that matter.

Scenario timelines

Combine sales, cash-out refinances, HELOCs, debt payoffs, purchases, and lease options in one ordered plan based on your portfolio.

Side-by-side strategy comparisons

Save each option as a scenario and compare ending net worth, monthly cash flow, debt, time to goal, and differences from your baseline.

Projected FIRE timing

FIRE progress is based on rental cash flow and a safe withdrawal rate covering your monthly expenses.

Scenario ranking with reasons

See which scenario ranks first, which inputs drove the result, and where the tradeoffs are close.

Monthly progress check-ins

Update balances and values each month, compare actual results with the projection, and maintain a history of net worth changes.

Property-specific planning rules

Protect a long-term rental from sale or refinancing recommendations, or mark another property as a debt-paydown priority.

Example comparisons

Compare your options using consistent assumptions.

“Should I use $40,000 for another rental or pay down a 7.1% mortgage?”

Create one scenario for each option, then compare cash flow, ending net worth, and FIRE timing.

“My duplex has limited cash flow and $150,000 of equity. What are my options?”

Compare selling, completing a cash-out refinance, and keeping the property under the same assumptions.

“Could a HELOC on my home fund the next purchase?”

Add the HELOC draw and interest rate, then schedule a purchase when cash covers the down payment. The projection includes the resulting debt service.

“When could passive income cover my expenses?”

Set passive income coverage as your goal. Each scenario shows when the goal is reached or whether it remains unmet during the projection.

Methodology

You can audit the math.

The model applies the same calculations to each scenario and documents how it handles funding, risk, and rental operating costs.

Funding shortfalls are identified

If projected cash becomes negative, the results identify the first affected month and the lowest cash balance.

Similar outcomes remain closely ranked

When two strategies receive similar scores, the comparison keeps them closely ranked instead of overstating the difference.

Consistent month-by-month calculations

Amortization and cash flow are calculated monthly. The same inputs produce the same results, and assumptions are listed with the projection.

Rental-specific assumptions

Projections can include vacancy, management fees, repairs, selling costs, and estimated capital gains tax on property sales.

Start free with your first property.

A free account includes 1 property, 3 scenarios, and 3 saved projections. Use them to compare a purchase with debt paydown, then upgrade when you are ready to model the complete portfolio.

Create your free account

Frequently asked questions

Who is this for?

Rental property investors with approximately one to ten properties who want to compare purchases, debt paydown, refinancing, HELOCs, and sales. This is portfolio planning software and does not include tenant portals or rent collection.

How is this different from a rental calculator?

A rental calculator evaluates one property or decision. Rental Wealth Simulator models properties, loans, and financial accounts together, including a sequence of planned transactions over time.

Is there a free plan?

Yes. The public calculators require no account. A free account includes one property, three scenarios, and three saved projections. Paid plans support a complete portfolio.

Where do the projections come from?

The month-by-month simulation uses amortization schedules, rental cash flow, vacancy and management assumptions, appreciation, and rent growth rates that you control. The same inputs produce the same results.

Will it just tell me what I want to hear?

No. A scenario is marked as unfunded if projected cash becomes negative. Similar results remain closely ranked, and the assumptions used in the comparison are listed with the results.

Do I need to connect my bank accounts?

No. You enter values directly and update them during monthly check-ins. You do not need to share bank credentials.

Compare your options before making a major portfolio decision.

Enter your current portfolio and review the projected financial effect of each option.