This tool helps answer the questions:
  1. Should I put more or less downpayment? Should I choose longer or shorter mortgage term?
  2. If I have enough cash to buy a house, but have higher-yield investment opportunities, should I use mortgage or make cash offer to purchase?
Mortgage Feature clear
Purchase price
Downpayment
Loan amount
Loan term years
Mortgage rate
Monthly mortgage payment
Mortgage Comparison
Plan A
Plan B
Downpayment
Loan term (years)
Mortgage rate
Investment yield the expected return of investment when you invest extra cash
Credit score range
Monthly mortgage insurance (PMI)
Monthly mortgage payment
Federal income tax rate (highest bracket)
Net present value (NPV) This is how much the NPV of using mortgage is higher/lower than the NPV of buying with all cash. When investment yield is higher than mortgage rate (APR), your NPV of using mortgage is normally higher than the NPV of buying with all cash, assuming your PMI is low. This is becasue your investment income is higher than the mortgage interest, and it brings you more cash inflow in the long term.
The winner plan The better Plan you should consider is the one with the higher NPV, it brings a better financial outlook in the long term. winner winner
All Cash Purchase (no mortgage)
Net present value (NPV) winner
This tool helps answer the questions:
  1. How much house can I afford, based on my budget, income, down payment, outstanding debts, and the debt-to-income ratio I want to maintain?
  2. How the mortgage rate, loan term, downpayment, closing fee, property tax, HOA & insurance afffect my affordability?
Income & Debt clear
Annual Income
Other debt payment / month
Current debt-to-income
Max debt-to-income
House & Mortgage
Mortgage rate
Loan term (years)
Downpayment
Closing fee
Mortgage insurance
Property tax
Home insurance / year
HOA / month
You can afford
House max purchase price
Loan amount
Initial payment
Monthly mortgage payment
Total monthly payment
Prospective debt-to-income
This tool helps answer the questions:
  1. Should I buy a house or keep renting? What is the cost and benefit difference at the end?
  2. If I plan to re-sell the house in a few years, would it still be good idea to buy, rather than to rent?
To Buy clear
Purchase price
Downpayment
Loan amount
Loan term (years)
Mortgage rate
Monthly mortgage payment
Monthly property income such as Airbnb, rent revenue.
Property value growth
Monthly mortgage insurance (PMI)
One-time extra costs such as closing fee, renovating cost.
Monthly extra costs Extra cost that you don't need to pay when renting, such as HOA, homeowner insurance (the amount over renter insurance), additional utilities, home maintenance.
Property tax of your city
To Rent
Monthly rent & fee
Sublease income
Rent inflation
Investment yield the expected return of investment when you invest extra cash
Other Inputs
Your highest tax rate (for elective deductions)
Re-sell after years at
Selling cost Normally the commission you need to pay to seller's agent and buyer's agent.
Buyer's gain (+) or loss (-)
to re-sell
not re-sell
Buyer's wealth
Renter's wealth
Wealth difference