Can i sue buy here pay here lot that keeps braking contract

The lot keeps changing the contract so they can repo my car, they said they can make provisions when they want too. i was up to date with payments and have insurance but my car is repo this week and they said i had a 50 dollar fee that i knew nothing about that is not on my receipt when i received it and when we asked why they did not bring it up they said they did not have too to tell us which we should of . We asked what do we owe when we made payment and they did not say a thing about this fee. they repo my car two months ago and said i had no insurance but i sent them the new insurance and they claimed they never got it, I am 11000 into my car and the more i pay the more they harass my family. Now they said because they have repoed my car too many times they said i have to pay it off or i cant get it back It has been a nightmare. I have a witness to their practices that worked for them but i cannot get a lawyer to help me in Pensacola Florida I need help before i lose my car