I paid what is market value at this point, which is 21,xxx-25,xxx, depending on year, condition and mileage. The S54's are still getting over 30k because of the motor. I purchased from a local dealership, so I put on an extended warranty, which is one of the reasons for me buying it from a dealership rather than private party.
I love the coupe, but I've never had a ragtop, so I figured why not? It helped that the wife said yes when I showed it to her.