Was looking at buying a used 2013 Specialized S-Works Tarmac SL4 for $2000. Bike was originally $7700 new and has obviously come down in value in the past 3 years. It is my size at 54cm. Looks nice in the pictures but i know they all look good initially. Is this a good price for this bike? Is there anything i should look for when checking out this bike? Thanks!