What is the difference between a fixed-rate and adjustable-rate mortgage (ARM)?

A fixed-rate mortgage keeps the same interest rate and principal-and-interest payment for the entire term. An adjustable-rate mortgage starts with a fixed period, then the rate can change at set intervals based on a benchmark index plus a margin. ARMs usually start cheaper but carry more payment risk later.

Should I refinance my mortgage?

Refinancing can make sense if you can lower your rate, shorten your term, or tap equity and you plan to keep the property long enough to recover closing costs. Compare your current payment and remaining interest with a new loan scenario using our Mortgage Refinance and Loan Payoff tools.

Mortgage & Real Estate Finance Hub

Q: What is real estate finance?

Real estate finance covers how residential or commercial property is funded, including mortgages, home equity loans, construction loans, and investment property financing. It focuses on how much you can borrow, what it costs over time, and how risky or profitable a property is.

Q: How much house can I afford?

Affordability depends on your income, existing debts, down payment, interest rate, and local taxes and insurance. Lenders often look for a debt-to-income ratio below about 36–43%. Use our House Affordability and Mortgage Payment calculators to test different scenarios before you talk to a lender.

Q: How do I evaluate a rental or investment property?

To evaluate an investment property, estimate rental income, subtract operating expenses and vacancy to get net operating income (NOI), then compare it to the purchase price and financing. Metrics like cap rate, cash-on-cash return, and IRR help you compare deals. Our Real Estate IRR, Cap Rate, and Cash-on-Cash Return calculators walk you through these steps.

Plan your home purchase, compare mortgage options, and analyze investment properties with a single interactive dashboard.

Quick Mortgage & Investment Planner

Adjust the sliders or type values to instantly see your estimated monthly payment, affordability, and basic rental property returns.

Home price / Property value ($)

Down payment (%)

20%

Interest rate (% APR)

Loan term (years)

Gross annual income ($)

Other monthly debts ($)

Show property tax, insurance & rent assumptions

Property tax (% of value / year)

Insurance (% of value / year)

HOA / maintenance ($/month)

Expected monthly rent (if investment)

Vacancy & credit loss (%)

Operating expenses (% of rent)

Mortgage snapshot

Loan amount: $320,000
Principal & interest (P&I): $2,022
Taxes & insurance (est.): $533
HOA / maintenance: $150
Estimated total monthly housing: $2,705
Total interest over term: $409,000

Affordability & DTI

Gross monthly income: $10,000
Front-end DTI (housing / income): 27%
Back-end DTI (housing + debts / income): 32%

Investment snapshot (if rented)

Net operating income (NOI): $0
Cap rate (NOI / price): 0%
Cash flow after debt service: $0
Cash-on-cash return: 0%

Key Mortgage & Real Estate Calculators

Deep-dive into specific questions with our specialized tools.

Mortgage Payment Calculator

Estimate monthly payments with principal, interest, taxes, insurance, and PMI.

House Affordability

See how much home you can afford based on income, debts, and down payment.

Rent vs. Buy

Compare long‑term costs of renting versus owning in your market.

Mortgage Refinance

Check if refinancing saves money after closing costs.

Real Estate IRR

Model multi‑year cash flows and exit value for investment properties.

Cap Rate & GRM

Evaluate rental deals using cap rate and gross rent multiplier.

How this mortgage & real estate planner works

The dashboard above combines three perspectives that lenders, investors, and homeowners all care about:

Payment view – What will my monthly housing cost be?
Affordability view – Does that payment fit my income and existing debts?
Investment view – If I rent the property out, what are my returns?

1. Mortgage payment formula

For a standard fixed‑rate mortgage, the principal and interest payment is:

Let:

P = loan amount
r = monthly interest rate (APR / 12)
n = total number of monthly payments (years × 12)

Then the monthly principal & interest is:

$ \text{P&I} = P \times \dfrac{r(1+r)^n}{(1+r)^n - 1} $

The tool adds estimates for property taxes, homeowners insurance, and HOA/maintenance to approximate your total monthly housing cost.

2. Debt‑to‑income (DTI) ratios

Lenders use DTI ratios to gauge how comfortably you can handle a mortgage:

Front‑end DTI = housing payment ÷ gross monthly income
Back‑end DTI = (housing + other monthly debts) ÷ gross monthly income

Many traditional lenders prefer:

Front‑end DTI ≤ ~28%
Back‑end DTI ≤ ~36–43% (varies by program and credit profile)

The planner highlights whether your scenario is typically considered comfortable, borderline, or high risk based on these ranges.

3. Basic rental property metrics

If you plan to rent out the property, the same inputs can be used to estimate:

Net Operating Income (NOI) – income from rent minus operating expenses (before loan payments).
Cap rate – NOI ÷ property value, a quick yield measure used by investors.
Cash flow after debt service – NOI minus annual mortgage payments.
Cash‑on‑cash return – annual cash flow ÷ cash invested (down payment and closing costs).

These are simplified estimates. For a full investment analysis, use our dedicated Real Estate IRR and Cash‑on‑Cash Return tools.

Common mortgage & real estate finance paths

The competitors you might see—large banks, government‑sponsored entities, and real estate portals—tend to focus on a single product or lender. This hub is lender‑agnostic and designed to help you compare options before you apply anywhere.

Owner‑occupied home purchase

Use House Affordability to set a safe price range.
Compare fixed‑rate vs. ARM scenarios with the Mortgage Payment calculator.
Estimate closing costs and cash needed at closing (down payment + fees).

Refinance or home equity

Run your current loan through the Mortgage Payment tool.
Model a new rate/term in the Mortgage Refinance calculator.
Consider HELOC or home equity loan scenarios for renovations or debt consolidation.

Investment & rental property

Estimate rent and expenses, then compute NOI and cap rate.
Layer in financing to see cash flow and cash‑on‑cash return.
Use Real Estate IRR for multi‑year projections and exit strategies.

Limitations & professional advice

The calculators on this page are educational tools. They do not replace personalized advice from a licensed mortgage professional, financial planner, tax advisor, or real estate attorney. Actual loan offers depend on your full credit profile, property details, underwriting guidelines, and local regulations.

Mortgage & Real Estate Finance FAQ

What is real estate finance?

Real estate finance is the set of tools and structures used to fund property—everything from conventional mortgages and government‑backed loans to construction loans, bridge loans, and investment‑property financing. It focuses on how much you can borrow, what it costs over time, and how risky or profitable a property is for both borrower and lender.

How much house can I afford?

A common guideline is to keep your housing payment under about 28% of your gross monthly income and your total debt payments under 36–43%. However, your comfort level, job stability, savings, and local property taxes all matter. Use this page’s planner plus the dedicated House Affordability calculator to test conservative and aggressive scenarios before you commit.

What’s the difference between fixed‑rate and adjustable‑rate mortgages?

A fixed‑rate mortgage keeps the same interest rate and principal‑and‑interest payment for the entire term (for example, 30 years). An adjustable‑rate mortgage (ARM) has a fixed introductory period, then the rate can reset periodically based on a benchmark index plus a margin. ARMs often start with a lower rate but carry more uncertainty later, which can be risky if rates rise or your income falls.

How do I evaluate a rental or investment property?

Start by estimating realistic rent, vacancy, and operating expenses (taxes, insurance, maintenance, management, utilities you pay). From there, calculate net operating income (NOI), cap rate, and cash‑on‑cash return. For more advanced analysis, model multi‑year cash flows and a future sale using IRR. Our Real Estate IRR and Cap Rate tools are built for exactly this purpose.

When does refinancing a mortgage make sense?

Refinancing can be worthwhile if you can lower your rate, shorten your term, or tap equity and you plan to keep the property long enough to break even on closing costs. Compare your current payment and remaining interest with a new loan scenario, then compute the break‑even point in months or years. Our Mortgage Refinance and Loan Payoff calculators help you quantify this trade‑off.