Skip to main content

Getting Started

mortgage-cli is a command-line tool for analyzing rental property investments. It helps you calculate break-even rent, evaluate investment viability, and compare different financing scenarios.

Features​

  • Break-even Analysis: Calculate the minimum rent needed to cover all costs
  • Sensitivity Matrix: Compare multiple price/down-payment combinations at once
  • Amortization Schedules: View detailed payment breakdowns over time
  • Profile Management: Save and reuse different investment parameters
  • Multiple Output Formats: Table, JSON, CSV, or narrative summary

Installation​

Using pip​

pip install mortgage-cli

From Source​

git clone https://github.com/jordanterry/mortgage-cli.git
cd mortgage-cli
pip install -e .

Quick Start​

Analyze a Property​

mortgage-cli analyze --price 150000 --rent 900

This calculates the break-even rent for a €150,000 property with an expected rent of €900/month.

Example Output​

┏━━━━━━━━━━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━┓
┃ Metric                   ┃ Value         ┃
┡━━━━━━━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━┩
│ Property Price           │ €150,000      │
│ Down Payment             │ 20% (€30,000) │
│ Break-even Rent          │ €885/month    │
│ Expected Rent            │ €900/month    │
│ Monthly Surplus          │ €15           │
│ Cash-on-Cash Return      │ 0.5%          │
│ Verdict                  │ GREEN         │
└──────────────────────────┴───────────────┘

Generate a Sensitivity Matrix​

mortgage-cli matrix --price-min 100000 --price-max 200000 --rent 1000

This shows break-even rent for different price/down-payment combinations.

Key Concepts​

Break-even Rent​

The minimum monthly rent needed to cover:

  • Mortgage payment (principal + interest + insurance)
  • Property tax
  • Building insurance
  • Maintenance reserve
  • Management fees

Verdict Colors​

ColorMeaning
GREENBreak-even rent is below 90% of target - good investment
YELLOWBreak-even rent is 90-100% of target - marginal
REDBreak-even rent exceeds target - poor investment

Profiles​

Profiles store your investment parameters (interest rates, costs, thresholds). The built-in default profile uses typical French property investment values.

Next Steps​

Tutorials​

New to mortgage-cli? Start with these step-by-step tutorials:

  1. Evaluating Your First Property - Learn the basics with a real scenario
  2. Finding Your Price Range - Use the sensitivity matrix to explore options
  3. Stress Testing Your Investment - Create profiles to evaluate risk
  4. Understanding Amortization - See how your mortgage works over time

Reference​