Buy vs. rent: What you'll pay in the 10 biggest cities. Boston

    One of the most densely-packed cities in the U.S., Boston's coastal location means that developers have limited space to build on.

    As a result, the city has some of the highest housing prices in the nation, a median of more than $400,000, according to Trulia. Rents are also stratospheric at more than $2,500 a month for a three-bedroom home.

    Low mortgage rates currently make buying a better bet than renting, but it's a closer call in Boston than in most of the other major cities. The savings advantage to buying in Boston is also shrinking. Last year, buyers were projected to save 40% over renters, thanks to lower mortgage rates and home prices.

% saved buying: 30%

Median home price : $435,000

Median rent: $2,550