You must look at such factors as your current income; your debts and the payments for each of them each month; your current monthly expenses; and what money remains to go to your mortgage payment. The second big factor that will affect your mortgage payment is the amount of your down payment. The larger your down payment, the less money you must borrow, reducing the amount of interest you pay. You also may be able to secure better terms for the mortgage amount. For further information, consult a mortgage lender.