Freon on 1994 Chevrolet Corvette

I was charged $139 just to put freon in my car. Was I overcharged??

Asked by for the 1994 Chevrolet Corvette
Not if it was done PROPERLY. That means a good visual inspection , evacuate , vacuum ( about 30 min.) and then re-charge with oil & dye. IF a leak is suspected , but not found on initial inspection , then the dye should help them find it in many cases.