that depends...........at the very least, you'd need 3.5% of the purchase price to go for an FHA loan...but that amount can increase to 5 or 10+ % more.........with a 20% down payment, you will not have the added expense of PMI (private mortgage insurance).
The real question is - how much of a loan do you qualify for?
Based on your income and debit ratio,and factoring in property taxes and insurance, the mortgage rep will tell you how much you can borrow.
So, once you sit down with a lender and get pre-approved for a loan, you will know where you stand.......
Then, as far as the down payment is concerned - that will be the amount you add in, in order buy in your desired price range.
Don't forget to factor in closing costs, too.
Please remember to have a cushion in the bank to cover unexpected repairs.............a minimum of 3-6 months of living expenses is recommended by most financial advisers..