When comparing two homes of similar size and ammenities, one for rent and one for sale, the rent is typically 15-35% higher than the payment would be on a 30 yr mortgage loan. This is based on an FHA loan with only 3.5% down.
Right now there are also several programs and incentives from sellers that can help you to purchase a home with less down than you would pay for rent + security deposit.
If you'd like more information on some of these loan programs feel free to call me. It's definitely worth looking into.