I brought my car to Pep Boys in Moorestown, NJ with a radiator leak, they diagnosed that my serpentine belt was loose, it needed a tensioner and a radiator flush/fill.
I know little about cars, but I know that if the serpentine belt isn't working correctly, it wouldn't be just the radiator malfunctioning but most of the other operations, too. Also, I checked the belt myself after they told me this - it was very tight and functioning properly.
Their charge for this repair: $475. I removed my car from their garage and took it to a trusted mechanic in Philly (which I should have in the first place, but didn't want to push my car too far when there was a problem). They told me - if the problem WAS the serpentine tensioner, the cost for that (parts+labor) would have been $113. THAT'S $300 LESS THAN PEP BOYS!!!
Turns out- that wasn't the problem at all, as I had thought. It needed new radiator elbows, a minor charge. Pep Boys are trained to lie and and suck the cash out of consumers. It has been this way at every Pep Boys I have patronized, and unfortunately I don't think it will change. They'll say anything or make up any repair to charge you more. Save yourself and do not trust them!