From a lender:
Your credit score can be as low as 620.
The better your score, the better interest rate.
You want to take 40% of your gross monthly income, back out your monthly revolving debts, car payments and student loans.
Take that final number and that will be your house payment.
In today's market a payment of $2500 is about a $450k mortgage.
I can run these numbers for you. Just drop me an email.