20% down rule, 36 month financing, 8% gross to payments, I’m coming up with a maximum value of about $11,059. It doesn’t have to actually fit in that box, but the maximum value is what I think is reasonable. You can finance for longer, or have less down payment, but you shouldn’t spend $20,000 in your situation.

I would also research rates with credit unions. In my market you can get 4.5% for a car under 10 years old. If the car is old the rate is about 7.5%.

You could let it roll at 13%, but I would get a second job and work like crazy for 12-18 months to rapidly pay that down. It’ll still establish your credit and you won’t pay as much of a penalty from interest. Another thing is you could refinance to a better rate as your credit builds. Your credit will drop, but should be higher than when you started by month 12 with perfect payment timeliness and everything else being equal.