SL 500 2008

Hi, the old man has been offered an sl500 2008 44k miles, for what seems a silly price don't know the spec at the mo but has a tv tuner so presume fairly well spec'd, what sort of money would be reasonable for an sl 500 of this age presuming fairly good condition MB service etc. Have seen from a quick browse what autotrader ads are asking.

Thanks
Dyverman
:D