1.conventional banks have very limited loans they give out and your debt ratio was probably too high for them
2.without looking at your tri-merge credit report it would be impossible to know your particular situation.
3.I do not suggest renting,from an investor standpoint it's great you get the potential homeowners to plop down thousands of dollars of non-refundable deposit,usually the renters treat the property better because there is a chance they might own it so they have a stake in the property,from the renters standpoint it's bad it puts your hard earned non-refundable deposit money into the landlord's hands and puts you in a weak position of negotiating power because the owner knows if you could buy you wouldn't be renting and 95 percent of the time you don't end up buying the house because you learned of defects you don't like,you end up splitting up,relocating,death in family,etc.It's much better to wait a couple of months improve your score and pay down your debt so that when you buy your coming from a position of negotiating power.
4.ask your creditors to raise your credit limits that can help raise your credit score.here is how most credit scoring models work.if your balance is more than 75 percent of your limit that negatively impacts your score,50 percent neutral,and less than 33 percent improves your score
5.some lenders will go as high as 56 percent debt ratio on the back-end but the interest rates are higher,there thought is if you are having to use most of your credit to stay afloat you are going to have a higher risk of defaulting when times get hard,hope this helps some.