Although some agents and bankers (and many realtor/lender websites) will surprise you with generous assessments of how big a mortgage you can afford, being a "good buyer" will make for a smoother shopping and purchase experience. Aim for a mortgage of 80 percent or less of the purchase price -- which will also save you money by avoiding a premium for MGIC Private Mortgage Insurance. FinanCenter, which is not associated with any particular lender, has a comprehensive collection of calculators and articles to evaluate your mortgage options. They can be really complex, so refer to Interest.com for syndicated columnist Jim Duboth's excellent articles on virtually every mortgage complexity -- such as adjustable rates, points, balloons, and self-employment documentation. Then start looking for your mortgage there, but don't let any loan arranger write one until you look into Bank Rate Monitor, the top-rated lending information site.