How the model works
The math.
The calculator runs a full discounted cash-flow on a ten-year hold, then reports four numbers most buyers actually care about: the internal rate of return in BRL, the same IRR re-expressed in USD after the currency curve, the equity multiple (how many times your cash returns over the period), and the first-year cash-on-cash. Cap rate and gross yield are shown as sanity checks — they're how Brazilian brokers usually quote, but neither captures appreciation, financing or exit, which is why IRR is the honest answer.
- DCF
- Each year's cash flow is laid out: gross rent, vacancy or occupancy haircut, operating expenses, mortgage interest + principal, income tax. Year 10 also includes the sale: property value compounded at the appreciation rate, minus selling costs, minus capital-gains tax on the gain.
- IRR
- The discount rate that sets NPV to zero across the cash-flow series. Computed via Newton-Raphson with bisection fallback; converges in <100 iterations on any realistic input.
- FX-adjusted
- For the USD-IRR, each BRL cash flow is converted at the projected BRL/USD rate for that year. A positive FX drift means BRL strengthens vs. USD — your dollars-back number goes up. The default of 0% holds the rate flat for a clean read.
- Equity multiple
- Total cash returned (annual cash flow plus net sale proceeds) divided by the cash you put in at close (down payment + closing costs + furnishing). 1.0× means you got your money back. 2.0× means you doubled.
- STR vs LTR
- Short-stay uses ADR × occupancy × 365, less management fee, less per-stay costs absorbed in the fee. Long-let uses monthly rent × 12, less vacancy, less management. Both share the same operating costs (IPTU, condomínio, insurance, maintenance reserve).
- Taxes
- Rental income tax defaults to 15% (the flat withholding rate for non-resident landlords; residents pay progressive carnê-leão rates up to 27.5%). Capital-gains tax defaults to 15% on the realized gain at sale. Both are user-adjustable. PJ structures and the IR isento threshold are not modeled — talk to a Brazilian accountant.
Two things the model deliberately leaves out, because they distort comparisons more than they help: depreciation tax shields (Brazil doesn't treat residential real estate the way the IRS does in the US, so the shield is small and complicated), and refinance scenarios (most foreign buyers in Rio are cash; financing is modelled as a single fixed-rate loan held to exit). If either matters for your structure, the calculator is the starting point of the conversation, not the end.
This is a model, not advice. The defaults are real numbers we underwrite to, but every Rio property is its own deal — the condomínio's short-stay rules, the building's occupancy track record, the IPTU bracket, what the comparable sales actually traded at. We're happy to run this on a specific apartment with proper inputs. Start a conversation.