Kfingar, your monthly payment will depend on the terms of your mortgage loan (APR, 15, 20, 30 yrs, etc..) You will be able to calculate an estimated $$ amount by visiting a website such as http://www.bankrate.com.
That site includes calculators for any type of loan, and will help you to determine the monthly payment. Please keep in mind that their calculators will not include the cost of property taxes or insurance! Take these figures into account when planning your budget.
Example: $77,000 @ 5.25% for 15 years = $618.00 (excluding taxes and insurance).
Hope this helps!