Loan Types¶

This tool supports a range of U.S. mortgage loan types. Each loan has distinct amortization rules, fees, and optional parameters.

Fixed Rate Loans¶

Fixed rate loans maintain the same interest rate over the life of the loan. These are the simplest to model and are ideal for borrowers seeking predictable payments.

Use with: --type fixed
Optional: --extra-payment, --extra-frequency

Adjustable Rate Mortgages (ARMs)¶

ARMs begin with a fixed-rate period and then adjust periodically based on an index (e.g. SOFR) plus a margin.

Use with: --type arm
Configure with: --index, --margin
Example: A 5/6 ARM has 5 years fixed, adjusts every 6 months

FHA Loans¶

FHA loans are backed by the Federal Housing Administration. They include:

Upfront MIP (1.75%) added to principal
Monthly MIP (0.85% annually by default)
Lower credit requirements
Use with: --type fha

VA Loans¶

VA loans are for veterans and active-duty military. Features include:

No PMI
One-time VA guarantee fee (default 2.25%)
More flexible underwriting
Use with: --type va

USDA Loans¶

USDA loans support rural homebuyers. They include:

One-time guarantee fee (1.00% default)
Annual fee (0.35%) added monthly
No PMI
Use with: --type usda

HELOCs (Home Equity Line of Credit)¶

HELOCs allow borrowing during a draw period followed by repayment:

Interest-only draw phase (e.g., 10 years)
Repayment phase (e.g., 15–20 years)
Adjustable rates typically tied to PRIME or SOFR
Use with: --type heloc
Configure draw/repay: --draw-period, --repayment-term
ARM-style index support: --index, --margin

Summary Table¶

Loan Type	PMI/MIP	Upfront Fees	Adjustable?	Notes
Fixed	Optional	None	❌	Stable and simple
ARM	Optional	None	✅	Rate changes after fixed period
FHA	✅	1.75% MIP	❌	Lower credit, extra fees
VA	❌	2.25% VA Fee	❌	For veterans only
USDA	❌	1.0% Fee + 0.35% annual	❌	For rural borrowers
HELOC	❌	None	✅	Draw + repay phases

See CLI Options for how to configure each loan type.