ValoPlex
The true value of your plex, door by door
A valuation engine built specifically for Quebec's income properties — 393,867 multi-unit buildings, 1.7 million doors, one scale-proof ratio hedonic model.
393,867
plex buildings covered
1,733,744
doors
91,060
plex sales
13.8%
median error (MdAPE)
80.0%
measured range coverage
$400.6B
total Quebec plex value
Overview
A plex is an income property: its value is reasoned per door, per revenue, per cap rate — not like a single-family home. ValoPlex covers every residential multi-unit building in Quebec, from duplexes to towers, with a model and interface dedicated to that logic, including per-door economics benchmarked against the local market.
The model targets log(price / assessed value) rather than raw price. A raw-price model dominated by the mass of duplexes crushes large buildings — one tower assessed at $705M was predicted at $5.6M. In ratio space, a $400K duplex and a $700M tower are valued with the same relative accuracy. Beyond 12 doors, estimates shrink toward empirical size-band anchors, and P10–P90 ranges use Mondrian conformal calibration per door band, with a measured — not promised — 80.0% coverage.
The interactive investor pro forma inverts the income approach: it derives the closed-form implicit rent the estimated value assumes, then builds a full operating statement, Canadian semi-annual mortgage, DSCR, cashflow per door, 5-year projection, break-even rent and rate, and interest-rate sensitivity — all recalculated live from five sliders.
Key Features
Per-door economics
Value per door, assessment per door, area per door, and land per door — each benchmarked against the local market.
Interactive investor pro forma
Implicit rent, full operating statement, Canadian mortgage, DSCR, cashflow per door, 5-year projection, break-even, and rate sensitivity — five sliders, live recalculation.
Full closing costs
Transfer duties under both the provincial scale and Montreal's enhanced scale (up to 4%), plus notary, inspection, and total cash-to-close.
Signature doors frieze
One SVG door drawn per unit, with a DUPLEX/TRIPLEX/…/MULTI-N-DOORS badge — the visual signature of every property page.
Scale-proof ratio model
Targets log(price/assessed value) so duplexes and towers are valued with equal relative accuracy, informed by roll-vintage age in months.
Mondrian conformal calibration
P10–P90 ranges calibrated per door band on a dedicated calibration set — 80.0% coverage measured, not promised.
Honest comparables map
A surveyor-plan SVG map with real azimuths and distances, plus a fourth per-door adjustment (50% of price/door, capped ±30%) — and an honest empty state when no comparable plex exists.
PDF report suite
Standard 3-page report with pro forma, 6-page bank-grade professional report, portfolio report, and a provincial statistical report.
Provincial plex statistics
Quebec's plexes are worth $400.6B — broken down by building size band and by municipality.
How It Works
Ratio hedonic model
Trains on log(price / assessed value) with roll-age awareness, producing predictions for 2021–2026 that stay accurate from duplexes to towers.
Out-of-domain shrinkage
Beyond 12 doors, where sales are rare, the model weight slides from 55% to 20% toward the empirical anchor of the building's size band.
Conformal calibration
P10–P90 ranges are calibrated per door band (Mondrian) on a dedicated set, achieving verified 80.0% coverage.
Comparables engine
Adds a fourth plex-specific adjustment — 50% of the comparable's price per door, capped at ±30% — on top of market, size, and age adjustments.
Pro forma library
A 20-test finance module derives closed-form implicit rent, Canadian semi-annual mortgage math, DSCR, break-even by bisection, and 5-year equity projections.
Application layer
Next.js 16 app over a SQLite base built by the Python pipeline, serving valuations, pro formas, statistics, and pdfkit reports.
Tech Stack
Application
Data
Model pipeline
Reports & testing
Highlights
- The ratio-target insight came from a measured failure: a raw-price model predicted a $705M-assessed tower at just $5.6M.
- Validated on 13,617 never-seen sales to the IAAO standard — 13.8% MdAPE overall, 12.6% on triplexes — plus a temporal test on 9,172 sales from 2026.
- 80.0% range coverage is measured on a dedicated calibration set, not assumed — Mondrian conformal calibration per door band.
- The pro forma inverts the income approach: closed-form implicit rent RB = (V·TGA + F) / (1 − vacancy − %variables), then a full investor statement.
- Computes that all of Quebec's plexes are worth $400.6 billion, broken down by size band and municipality.
- Companion product to Vrai-Prix — same editorial-sharp design language, orange accent instead of red, 33/33 tests passing.
Explore ValoPlex
Plex valuation, door by door — the full source is on GitHub.