I noticed that whenever I used a site such as kbb or nadaguides, it only gives me a retail value for a used bike. This is a private party transaction, of course, and I'm not sure how much lower to expect. FYI, I'm looking at an '02 SV650S, blue. Mileage 13k (above average according to KBB). Bike otherwise in perfect condition. KBB and nadaguides say about $4150.. but again, that's retail value and for lower mileage. How do you guys price bikes?