I purchased a house at age 23. I had a DTI of about 40% a FICO of about 650 and put nothing down. I purchased the house through a mortgage broker and got a 2 year locked, 30 year variable loan at 8.99% through a company called NovaStar. After 2 years they sold our mortgage to a company called Saxon that was just ridiculous, they raised our interest rate to 13.99% and constantly held our payments to accrue interest.
I went to my credit union and was surprised to find that they have very relaxed requirements as compared to banks. I refinanced my house to 4.99% (with 3 points that I also rolled into the mortgage) for a 30 year fixed mortgage. My payments are the same as it was for the previous 8.99% except now we have an escrow for insurance and taxes.
I cannot emphasize enough, the benefits that come from mortgaging a house (or establishing a car loan) through a credit union. Some are hard to get into but ask around, if any of your family members are enrolled, you can as well, in addition you may have eligibility through your place of work. I recommend looking up a credit union, seeing what they have to offer, then using that to compare to what Bank of America has to offer.
One last thing, banks offer rates that are usually best case scenario, for instance, BOA has a 3.99% rate, but if you apply you may end up being offered a 6% if you don't qualify for the lower one. At credit unions they will give their lowest rates to everyone that qualifies.