Tax and insurance
When a loan has an escrow account, the property tax and homeowners insurance come out of a portion of each mortgage payment. The CFPB points out that these amounts are not fixed: tax bills and premiums can rise or fall, and the escrow payment moves with them.
Maintenance
Repairs and upkeep fall on the owner. There is no official figure for what a given house needs, so the calculator asks for your own estimate in dollars.
Closing costs
Federal rules give the lender three business days after your application to deliver the Loan Estimate, and the Closing Disclosure must reach you no later than three business days before consummation. On the Loan Estimate, the estimated total you bring to closing carries the label «Cash to Close». For the calculator, enter the closing costs without the down payment, which has its own field.
Mortgage insurance
Some loans carry mortgage insurance every month. Put the figure from your quote in its own field.
Selling later
Selling has costs of its own, such as agent commission and transfer taxes. The calculator subtracts the percentage you enter from the home's value at the end.
How official statistics see it
The Bureau of Labor Statistics measures an owner's shelter cost mainly as implicit rent: what owner occupants would have to pay if they were renting their homes, without furnishings or utilities. It is a useful reminder that the home itself also provides something each month.