FDU-INS French Property Investment Analyzer
Analyze French rental property investments with detailed cash flow projections, ROI calculations, and break-even analysis.
Quick Start
The calculator runs via Python script with JSON input/output:
echo '{
"propertyPrice": 300000,
"downPayment": 60000,
"interestRate": 3.5,
"loanTermYears": 20,
"monthlyRent": 1500,
"holdingPeriodYears": 10
}' | python3 french_mortgage.py --json-input
Returns comprehensive JSON with mortgage details, yearly projections, and investment summary.
Required Parameters
| Parameter | Description |
|---|---|
propertyPrice |
Property purchase price in EUR |
downPayment |
Down payment in EUR |
interestRate |
Annual interest rate (%) |
loanTermYears |
Loan term in years |
monthlyRent |
Monthly rental income in EUR |
holdingPeriodYears |
Investment holding period in years |
Optional Parameters
See reference.md for complete parameter list including property tax, HOA fees, maintenance, management fees, vacancy rate, and rent increases.
French-Specific Costs
The calculator automatically includes:
- Arrangement Fee: 1% of loan amount
- Registration Fee: 1.5% of loan amount
- Survey Fee: €750 fixed
- Life Insurance: 0.4% annually (in monthly payment)
Common Use Cases
For detailed examples of comparing properties, sensitivity analysis, and handling complex scenarios, see examples.md.
Key Output Metrics
- Monthly Payment: Mortgage + life insurance
- ROI: (Net profit / Initial investment) × 100
- Cash-on-Cash Return: Annual cash flow / initial investment
- Break-Even Year: When cumulative cash flow becomes positive
- Equity Build-Up: Down payment + principal paid
How to Use with Claude
When the user mentions French property analysis, extract parameters from natural language and run the analysis.
Example user request:
"What's the ROI on a 300k property with 20% down, 3.5% interest, renting for 1500/month?"
Extract and run:
echo '{
"propertyPrice": 300000,
"downPayment": 60000,
"interestRate": 3.5,
"loanTermYears": 20,
"monthlyRent": 1500,
"holdingPeriodYears": 10
}' | python3 french_mortgage.py --json-input
Present the ROI, monthly payment, cash flow, and break-even year from the results.
Additional Resources
- reference.md - Complete API documentation
- examples.md - Usage examples and common scenarios