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Multi-variate yield simulator.

Deterministic scenario engine — rental-property economics

Every combination of occupancy and nightly rate, computed and visualized — so a property decision rests on the full landscape of outcomes, not a single spreadsheet guess.

01 — What it is

The whole outcome space.

The simulator evaluates the annual yield of a dual-unit rental property (a main room plus a lock-off unit) by sweeping four variables — main-room occupancy, lock-off occupancy, main-room nightly rate ($150–$500), and lock-off nightly rate ($100–$250) — through every step of their ranges. That produces 3,520 fully-computed scenarios, each carrying gross revenue, operating costs, net income, and yield on purchase price.

A note on the label: this is a multi-variate grid sweep, not a Monte Carlo simulation. Monte Carlo draws random samples from probability distributions; this engine exhaustively computes every scenario in the grid exactly once. The result is deterministic and reproducible — same inputs, same 3,520 answers, every time. For a bounded four-variable space, exhausting the grid is strictly more informative than sampling it.

02 — Try it

Live simulator.

Runs entirely in your browser — nothing is uploaded, no account needed.

03 — User guide

Four ways to read the landscape.

i

Swarm

An animated dot plot of all 3,520 scenarios, each positioned by its yield — see where outcomes cluster and where the tails live.

ii

Distribution

A histogram of yield frequency — how likely each band of returns is across the whole scenario space.

iii

Matrix

A heatmap of occupancy × nightly-rate combinations — spot the thresholds where the economics flip.

iv

Interactive

Real-time sliders for all four variables — dial in any scenario and watch revenue, net income, and yield respond instantly.

  1. Pick one of the four view tabs across the top of the simulator.
  2. Start with Swarm or Distribution to understand the overall shape of possible outcomes.
  3. Move to Matrix to find which occupancy and rate combinations clear your target yield.
  4. Finish in Interactive — set the sliders to your expected scenario and read gross revenue, net income, annual yield, and where that outcome ranks as a percentile among all 3,520 scenarios.

04 — Under the hood

Model & assumptions.

Fixed parameters baked into the current model (editable in the source):

ParameterValue
Purchase price$414,000
Unit size85.84 sqm
Monthly HOA$8.50 / sqm
Credit-card commission2.5%
OTA commission12%
Electricity4% of revenue
Insurance rate0.5%
Guest services$11 / night
Maintenance reserve4% of revenue
Owner share80% of net revenue
Gross revenue = (main ADR × main occupancy × 365) + (lock ADR × lock occupancy × 365) Hard costs = CC fees + OTA fees + guest services + maintenance reserve Net revenue = gross revenue − hard costs Owner share = net revenue × 80% Annual costs = HOA + property tax + insurance + electricity Net income = owner share − annual costs Yield = net income ÷ purchase price × 100