We are well aware of the unreliability of Zillow.com’s “zestimates” of home values in Marin, but this post on their blog is pretty cool. They’ve crunched the data to show how many years it would take to break even on the cost of buying versus renting the same home in metro areas around the country, including the Bay Area. The numbers are pretty low in areas where home prices are relatively low compared to rents, and much higher in expensive markets. For example, they say that in Novato just 4.5 years after buying a house you would start to save money versus renting, while in a market like Tiburon they calculate it would take more than 15 years to reach the break even point. Here’s a direct link to the SF and Marin numbers.