I am looking to buy an Audi S4 and was wondering if cars that have had significant modifications take away from the value of the car at all? For instance, here is one I like.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&sspagename=ADME%3AL%3ARTQ%3AUS%3A1&viewitem=&item=300066462972&rd=1

Thanks,

Gary