Well, one of the things working against you is that student loan. The debt service on that loan is pretty large I'd imagine, and will be counted in the ratios they use to qualify people for loans. However, the loan for your parents place won't show up unless your name is on the mortgage which is nice because whatever portion you pay on it now won't be counted as part of your debt service. Judging by the fact that they are upside down and previously filed for bankruptcy, I'd start seeing if I could qualify on my own for a house of my own. However, if you intend to still help them out by paying part then you'll want to make sure you can afford your contribution, plus all existing debt service, in addition to the payments on whatever new house you find.
I recommend you find a lender nearby, perhaps a community bank, and start trying to form a relationship. Be upfront, tell them your position and ask what you would need to do to get to where you want to be. They can quickly tell you how much you're able to prequalify for based on income and debt, and then you know what range to look for. Buy, live in, move out, rent, rinse, repeat.