Property decisions involve large numbers and small percentages, which is exactly where mental math goes wrong. This calculator for landlords and homebuyers lets you write the price, the rate and the rent once and build every other figure from them, so comparing two listings means changing two lines.
Every example shows the answers Notes Calculator gives. Choose Open in Notes Calculator under any of them to open it in the web app.
Down payment and loan size
Start from the asking price, take your down payment (the deposit) as a percentage of it, and the rest is the loan. Closing costs are often a few percent of the price.
| Note | Result |
|---|---|
| price = 350k USD | $350,000 |
| deposit = 20% of price | $70,000 |
| Loan: price - deposit | $280,000 |
| Closing costs at 3%: price * 3% | $10,500 |
The monthly mortgage payment
Write the amortization formula in steps: the monthly rate, the number of payments, and the growth factor.
| Note | Result |
|---|---|
| loan = 280,000 USD | $280,000 |
| r = 6.5% / 12 as % | 0.54% |
| n = 30 * 12 | 360 |
| factor = (1 + r) ^ n | 6.99 |
| Monthly payment: loan * r * factor / (factor - 1) | $1,769.79 |
The loan payment guide shows how much of each payment is interest and how a shorter term changes the total.
The full monthly cost of owning
The payment is only part of it. Label each monthly cost and total them.
| Note | Result |
|---|---|
| Mortgage: 1,770 USD | $1,770 |
| Property tax: 380 USD | $380 |
| Insurance: 120 USD | $120 |
| Maintenance: 250 USD | $250 |
| total | $2,520 |
Rental cash flow
For landlords, subtract the mortgage, taxes, insurance and a repair reserve from the rent. The reserve is a share of the rent you set aside every month.
| Note | Result |
|---|---|
| rent = 2,100 USD | $2,100 |
| mortgage = 1,180 USD | $1,180 |
| taxes = 260 USD | $260 |
| insurance = 90 USD | $90 |
| reserve = 8% of rent | $168 |
| Cash flow: rent - mortgage - taxes - insurance - reserve | $402 |
Gross yield and a rent increase
Compare listings by the year’s rent as a share of the price, and see what a rent increase brings in.
| Note | Result |
|---|---|
| purchase price = 280,000 USD | $280,000 |
| monthly rent = 2,100 USD | $2,100 |
| Gross yield: monthly rent * 12 / purchase price as % | 9% |
| After a 3.5% increase: monthly rent + 3.5% | $2,173.50 |
For a household budget around the new payment, see the budget calculator guide, and for the area of a lot or a floor plan, the area calculator guide.
Start free at app.notescalculator.com, or see what Lifetime adds if you want a note per property or listing, synced across your devices.