The most important housing decision that most consumers face is whether to rent or to buy. So to help them with this decision, we took a look at the key market factors affecting the cost of homeownership. First off, asking home prices have started to rebound and have risen by 2.3% year over year in August (3.8% excluding foreclosures); however, rents have risen more (4.7%). This means that prices are lower relative to rents than they were a year ago. But more importantly, mortgage rates have fallen: the best rates this summer have been around 3.5%, while last summer rates were closer to 4.5%. Based on asking prices and rents during the summer of 2012, buying is now 45% cheaper than renting in the 100 largest U.S. metros, on average – that’s a savings of $771 a month. If you plan to stay in a home for 7 years, which is the average time that Americans traditionally live in a home before moving again, it is more affordable to buy than to rent in ALL of the 100 largest metros in the U.S.