if you buy from a dealer there is a warranty whether they say there is or not , on say a 2002 car , there would be at least a 3-6 month warranty on major components in a courts eyes (that is if was taken that far), on newer cars there would be 6 months ,no arguments
That is why generally it is more expensive to buy from a dealer , they have to work a contingency fund into the price as well as a profit margin