Determine your price range
How much house can you afford? If you have a trust fund or you own a software company, this is an easy step. Otherwise, you'll have to consider issues like how much of a down payment you can get together (20 percent of the sale price is a safe amount, although you can get away with less if you need to), how much you can afford to put toward housing every month (the general recommendation is 28 percent to 33 percent of your income), and how much debt you can afford to pay off (up to 36 percent of what you earn) [source: CNN].
For an in-depth calculator, check out CNN Money: Home Affordability.