This is a common problem and this is why the dealers like to close customers on the monthly payments. What they do is they pull your credit and lets say that you qualify for an interest rate of 10%, when they show you the monthly payment they calculate it at 13% and use that 3% leg to "sell" you extras or in your case just cram them in without your knowledge hoping that you will not notice.
What you will have to do is send them a certified letter RRR and tell them that you were never told that about the extras and never knowingly agreed to purchase them and that you want all remaining items removed from the transaction and want the contracts redrafted accordingly. (Just as an aside, I would buy gap insurance from elsewhere, like your own insurance co. it is really cheap and worth every penny)
You will have to tell them that they have 5 business days to comply before you will start taking action in the form of reporting their conduct to the Better Business Bureau, the state attorney general's office - consumer protection division, and to online consumer protection sites like The Ripoff Report. Also let them know that you are prepared to take legal action after you publicize their conduct.
You can file a civil suit for fraud, misrepresentation, breach of contract, and deceptive trade practices and may be able to shitf legal fees and costs against the dealership.
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