I'm Lucy, and I'd be happy to answer your questions today. I'm sorry to hear about your situation.
You can simply not pay them. They have a legal right to sue you for any unpaid balance after the repossession, but if your only income is SSI and retirement accounts, they will have no recourse against you. Retirement funds and SSI cannot be garnished to pay a debt. You should be aware, though, that an unpaid judgment will remain on your credit for 7 years, and it can be renewed for another 7. If you own your own home, they could put a lien on the property, so that might not be an option for you. However, the first $5,000 in equity is exempt from being taken to pay a judgment.
Another option is to wait and see how much they're asking for after the call sells, tell them that you're "Judgment proof" (That's the legal term), and offer to settle for some amount you believe is fair in exchange for their promise not to sue for the rest. That promise is enforceable as long as you get it in writing.
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