Dishonest Sales & Service

I purchased a used vehicle and dealer has denied any repairs within the first 30 days of purchase. Within first week a crack on windshield became noticeable. Dealer declined repairing. Safelite informed me crack has been there and was covered up so I had to replace the entire windshield within first 7 days. Then brakes began to squeak loudly and transmission wasn't shifting properly. Had a second opinion for these issues and found rust on brakes and that transmission fluid had been over filled. Brought car back to dealer on the 23rd day and was denied repairs again citing nothing is wrong and that rust is expected and that second opinion people are wrong. I know there are problems with the car cause I'm driving it! To be denied help within the first 30 days of purchase is just wrong. Clearly these issues were there and weren't disclosed to me at purchase or covered up so I wouldn't notice at time of purchase. My warranty cannot cover repairs for pre existing conditions. Now I'm paying for repairs that should have been made by the dealership.