Repossession: Voluntary Repo Issues

My question involves a consumer law issue in the State of: Florida

I purchased a truck from a local buy-here-pay-here place. I have done business with them before and while their interest is high, they have provided me with generally good experiences.

Unexpected medical issues and bills made it very difficult for me to pay the payments, so I explained the situation. Rather than have them drive out and repossess the truck I turned it over. They have since resold the vehicle for exactly what I paid for it.

I contacted them about a refund for the difference between what they sold it for and what I owed. They told me that when a customer turns in a car it is not a repossession. They also told me that they don't owe a refund on the interest even though I only had the truck for 6 weeks and they charged 4 years of interest on the simple loan.

Finally, I argue that since they are both bank and seller they have to consider the interest they are charging the new buyer when calculating the difference between what I owe and what they sold it for.

I suspect that #3 is a bit of a reach, but how is it not a voluntary repossession, and how can they charge a full 4 years of interest for what amounts to a 6 week loan?

Any thoughts?

Repossession: Voluntary Repo Issues