Lending standards go beyond scores so there isn't really a list, we see folks with scores in the 500's get 3-4% interest loans and folks with 620-630 that get 8%. DCU is a good credit union to work with for most, Penfed is also good and my favorite is NFCU if you can get into. Most communities have a local credit union so that might be a good option. On your student loans you might want to consider income based repayments, also if your SSI is based on disability you might be able to get those loans forgiven partially or totally.
For auto manufactuers they use captive lenders that vary a quite a bit on lending standards so they can be a good option. All manufactuers have good lenders, you just have to keep an eye on the dealers because they mark up interest, that is one of the reasons that I suggest having a pre qualified loan before you walk in the door, let them beat a credit union rate. If your a member of costco they have a good service that negotiates prices that most cannot beat on their own. If your current car is paid off and has a trade in of $2,500 I would sell it privately, make more money and simplify your deal. Dealers steal trade ins, its just part of their business. If your car value is that low its one they will send to an auction so they will cover their bases by lowballing you. Bringing some cash for a down, pre approved financing and a prenegotiated price based on volume is the best way to make sure you get a good overall deal. Also pass on all of the protection plans a warranties. If you buy good modern car (non-german) chances are extremely low you will ever use that stuff and they are a major profit center for the dealers.
