A Django-based web application for personal passive real estate investors — buy-and-hold investors who want to analyze single-family rentals, small multifamily properties, and BRRRR deals with professional-grade underwriting. No fluff, no auction monitoring, no market timing — just durable cash-flow analysis.
Latest release:v0.4.0 (development milestone)
- Deal pipeline — Screen, offer, renovate, close, and lease properties through a visual pipeline workflow with 9-criteria screening
- Discovery source models — Structured ingestion for HUD REO (ArcGIS Hub), USDA REO, Dallas County NTS, and ATTOM preforeclosure notices
- Pipeline screening — Hard-kill and yield scoring for HUD/USDA/county sources; "Add to Pipeline" flow from list/detail views
- Growth area explorer — Discover and compare markets by demographic and economic indicators with pagination and CSV export
- VRM foreclosures — Foreclosure listings with direct linking to pipeline discovery
- Property underwriting — Full scorecard (CoC, Cap Rate, DSCR, GRM), BRRRR calculator, hold projections, tax modeling
- Market intelligence — Price-to-rent ratio, population growth, employment diversity, school ratings, walk scores
- Auto-versioned releases — Git tags → Docker bake → structured logging; every build carries its version
- Python 3.14 + Django 6.0 — Fully migrated to latest stable runtimes
- County foreclosure notice scraper framework (additional counties)
- Property comparison and portfolio scenario modeling
- Enhanced notifications and collaboration features
- Additional data source integrations (Redfin, Zillow)
- Deal Screener Dashboard — At-a-glance KPI grid (CoC, Cap Rate, DSCR, GRM, Score) with color-coded verdicts
- Property Entry Form — Clean, responsive form with styled inputs, smart grids, and real-time validation
- Property Detail Scorecard — Full underwriting score breakdown with pass/fail flags, verdict badge, color-coded metrics
- BRRRR Calculator — Client-side calculator with zero-ARV guard, verdict banner, DSCR warning, locale-formatted numbers
- Markets Page — Price-to-rent ratio, population growth, employment diversity, overall market score per ZIP
- Underwriting Score v2 — Multi-signal scoring (1% Rule, CoC, DSCR, Cap Rate, GRM, After-Tax CoC) with verdict
- Investment Analysis — Financial KPIs (Cash-on-Cash, Cap Rate, NOI, IRR, DSCR)
- Hold Period Projections — Year-by-year rent growth, equity build-up, appreciation scenarios, net sale proceeds
- Depreciation & Tax Modeling — 27.5-year straight-line depreciation and after-tax cash flow
Built on a bespoke design system — zero Bootstrap or third-party CSS frameworks:
| Token | Purpose |
|---|---|
--font-sans / --font-mono | Typography stack |
--color-primary / --color-grow-* | Semantic palette (action, success, caution, risk) |
--color-verdict-* | Underwriting verdict colors (A/B/C/moderate) |
--surface-page / --surface-card / --surface-secondary | Surface hierarchy |
--radius-sm / --radius-md / --radius-lg / --radius-pill | Corner rounding |
--sp-1 through --sp-8 | Spacing scale (4 px increments) |
--text-xs / --text-sm / --text-base / --text-lg / --text-xl | Type scale |
--border-default / --border-subtle | Border weights |
Components:.card, .kpi-grid, .data-table, .verdict-badge, .score-bar, .tab-bar, .layout-2col, .page-header, .filter-bar, .chip, .btn, .btn-primary, .form-input, .form-grid-2/3/2-1/2-1-1, .empty-state, .flag-list, .message, .brrrr-banner, .result-emphasis, .form-divider, .form-subsection-label
| Environment | Name | Best For | Database | Start Command |
|---|---|---|---|---|
| local | dev | Daily development on your machine | SQLite (db.sqlite3) | docker compose up -d |
| devcontainer | test | GitHub Codespaces / VS Code Dev Container | SQLite (/home/vscode/db.sqlite3) | Open in Codespace → make dev |
| render | prod | Production deployment | PostgreSQL (managed) | Click "Deploy to Render" button |
git clone https://github.com/paruff/prei.git
cd prei
cp .env.example .env
# Edit .env — set SECRET_KEY, DJANGO_ENV=development
docker compose up -d
# Open http://127.0.0.1:8000# Login: demo@prei.dev / DemoPass123!
docker compose up -dautomatically runs migrations and seeds the demo user — no extra steps. Windows users: See Local Docker Setup Guide for WSL2/memory config.
- Open repo in GitHub Codespaces (Code → Codespaces → Create codespace on main) or VS Code Dev Containers (Reopen in Container)
- Wait for build (~2 min), then run in terminal:
make dev
make devrunsmigrateandseed_dataautomatically — the demo user will be created for you. - Open forwarded port 8000 →
http://localhost:8000
Demo login:demo@prei.dev / DemoPass123!
The render.yaml blueprint provisions:
prei-web— Django app via Gunicornprei-db— Managed PostgreSQL
Required env vars in Render dashboard:
SECRET_KEY— generate withpython -c "import secrets; print(secrets.token_urlsafe(50))"ALLOWED_HOSTS— your Render URL, e.g.your-app.onrender.com
| Key | Purpose | Get Key | Required For |
|---|---|---|---|
ATTOM_API_KEY | Property details, comps, foreclosures | api.attomdata.com | Comps, property enrichment |
CENSUS_API_KEY | ZIP demographics, population, income | api.census.gov | Growth area scoring |
BLS_API_KEY | County unemployment, wages (QCEW/LAUS) | data.bls.gov/registrationEngine | Growth area scoring |
FRED_API_KEY | State employment growth, economic data | fred.stlouisfed.org/docs/api/api_key.html | Growth area scoring (fallback) |
HUD_API_KEY | Fair Market Rents by ZIP/county | huduser.gov/portal/dataset/fmr-api.html | Rental estimates |
GREATSCHOOLS_API_KEY | School ratings | greatschools.org/api | Neighborhood quality |
WALKSCORE_API_KEY | Walkability scores | walkscore.com/professional/api | Neighborhood quality |
Add keys to .env (local/dev) or Render dashboard (prod). See API Keys Reference for details.
Full documentation at https://paruff.github.io/prei/ (Diátaxis framework):
- Tutorials — Getting Started
- How-to Guides — Local Dev · Dev Container · Render Deploy
- Reference — Financial KPIs · Data Sources · API Keys
- Explanation — Architecture · Design System
Build locally:
pip install -r docs-requirements.txt
mkdocs serve- Lint/Format: ruff
- Type Check: mypy
- Tests: pytest + Makefile validation (no duplicate targets, proper syntax)
- Docs: MkDocs Material
- CI: GitHub Actions (
.github/workflows/) — DORA-friendly logging
Host the web application and all related code, tests, infra config, and documentation for passive residential real estate investment analytics — buy-and-hold SFR/small multifamily, BRRRR, and market intelligence.
Licensed per repository terms.