Need help pls.

I swapped my car to a private seller. We tested both cars and agreed that its is in good condition. I have it checked by my cousin whos familiar with car. I signed an aggreement that I am swapping the car in as is where is basis. Done deal. After few days I decided to bring the car to the casa and have it checked and I found that theres a lot of issues.  Can I still returned it? Or can I still do something about it because I need to spend a lot to get everything fixed. Thank you. I tried to contact the seller but he said that the deal is done and theres no warranty for the car. Help pls. I know buying or swapping to a second hand car is a buy at your own risk scenario. I kow its my fault that I wasnt able to thourough check the car, the prev owner said that he only knows how to drive the car and no time to bring it to mechanic, I though its just a few issues but theres a lot. What is the meaning of as is where is basis?is it applicable for swapping or trading as well?

Sadly, the law will not step in to save you from bad decisions. It might not be as bad as you think. Casas tend to over sell repairs

I also found out that the car has LTO alarm, the prev owner said that they dont know that it has an alarm, it was the veryfirst owner who put an alarm on that car. We swapped car back in April 15, acoording to LTO alarm was dated May 22.