bought mine new (008 FLHRSE4, 105th Anniv, Copper/Black new, serial no 1096/1800); besides the factory recall for the head gaskets which were done (replaced) in advance of any head gasket leakage at around 5k miles, I had the two front rotors replaced at or near 10k miles (also warranted by my dealer). No other problems, no breakdowns, no repairs needed.....the MC is regularly services (fluids changes) which is performed by my trustworthy HD dealer (no, IMO not all HD dealer service depts are honest based upon my experience).
i would suggest that you 1) require all service records from the owner, 2) check with your HD dealer's service dept as their maintenance mgmt software will show all works done against the VIN (all work done by auth HD dealers that is), and 3) have the MC inspected fully by a senior HD service tech....
last thing you want is to "get the fever" and buy one that you should have passed on considering so many are out there for sale...i.e.
www.chopperexchange.com,
www.cycletrader.com, etc.
good luck and good riding