Aspiring homeowners in several major cities, including those in the Boston area, are facing big hurdles as the cost of owning remains more expensive than renting.

The cost of homeownership in Boston, Los Angeles, Seattle, San Francisco, Portland and Oakland continues to be more expensive than renting; however, it may make more financial sense to buy depending on the situation, according to real estate website Trulia.com.

Trulia released its Q2 2011 rent vs. buy index, which compares the cost of buying and renting a two-bedroom apartment, condominium or townhouse in the nation’s 50 largest cities. Since last quarter, buying a home has become more affordable than renting in nearly four out of five (80 percent) major cities.

Boston ranked third with a rent-to-buy ratio of 19 in the second quarter. A price-to-rent ratio if 16-20 indicates the total costs of homeownership are greater than the costs of renting, but it might still make financial sense to buy depending on the situation, according to Trulia.

"With home prices nearing a double dip and more foreclosures expected to flood the housing market over the next two years, the decision between renting and buying a home across most of the country has clearly moved in favor of buying," said Ken Shuman, head of communications at Trulia. "As we head into the summer buying season, those looking to buy a home should be encouraged by improvements in the market and feel optimistic about their chances of finding an affordable home, much more so than in previous years."

He added: "Aspiring homeowners should focus their energies on locking down a low mortgage rate sooner than later. While home prices are unlikely to return to pre-crash levels, today’s low interest rates will likely rise thanks to inflation and spikes in the Fed rates. As the government wind downs its role in the mortgage markets higher mortgage interest rates will be inevitable."