A residential mortgage is a loan that homeowners use to purchase a residential property, such as a house or a condominium. The borrower agrees to pay back the loan with interest over a set period of time, usually 15-30 years. The lender uses the property as collateral for the loan, which means that if the borrower fails to make payments, the lender can foreclose on the property.

Lenders consider several factors when determining whether to approve a mortgage application, including credit score, income, employment history, debt-to-income ratio, and the amount of the down payment. A good credit score, stable income, and a low debt-to-income ratio can increase your chances of getting approved for a mortgage.

A pre-approval for a mortgage is a preliminary evaluation by a lender of a borrower's creditworthiness, based on a thorough review of the borrower's financial history and credit report. A pre-approval usually involves a hard credit check and provides a more accurate estimate of how much a borrower can afford to borrow. A pre-qualification, on the other hand, is a less rigorous evaluation based on self-reported information provided by the borrower.

Some common mistakes to avoid when applying for a residential mortgage include applying for new credit before closing on the mortgage, making major purchases before closing, and neglecting to shop around for the best mortgage rates and terms. It's also important to review all mortgage documents carefully and ask questions if anything is unclear.

The time it takes to get a residential mortgage varies depending on the lender, the complexity of the loan, and the borrower's financial situation. Generally, the process can take anywhere from 30 to 60 days, but it can be shorter or longer depending on the circumstances.