When you apply for a mortgage, your lender will do some quick math to figure out how much of a loan you can afford. Your lender will consider many factors, and one of the most important ones is your debt-to-income ratio. It is usually shortened to DTI, and understanding this formula can help you better understand how big of a house you can afford.  An Overview Of A DTI Your DTI represents the amount of money you spend compared to the amount you make. Your lender is going to have very strict DTI requirements when deciding whether you can be…