Complaint Review: Florida cars USA

My first time buying a car I went with florida cars USA Big mistake with a capital B, I put down 4000$ as down payment negotiated a 15000$ car advertised on Craigslist down to 12000$ And signed the papers so far so good right...Wrong  come to find out some of the papers I signed were blank like the one that was suppose to have a price was blank  later on I find out Those papers did not stay blank they put the price of the car at 21000$  which was the price of the car if  it was brand new which it was not my interest rate was 24% not what we discuss surppose to have been 15% why the bank financed such an outrages deal well that's because they were part of it because when I called them explaining what happen all I got was should have read your contract the name of that bank is national auto lendars  I remember the sells man smiled and nodded his head at an other dealer as I turned , at the time I thought it was because he was happy he just made a deal but now I know it was because he was laughing he just got another sucker.