I've purchased 2 pams from the sales boards recently and have had one with stripped guard screw housing and one with stripped lug screw housing. Not a huge deal and certainly buyer beware, but just a suggestion for sellers:
List known problems and adjust price accordingly.
Look carefully at the watch and check for common problems (that doesn't take long), especially if your just turning a watch.
Give the buyer a bit of history, if you know it (first,second owner, dealer (name) approximate age of the watch and mabey score it a percentage 100 being never worn.
Finally, that thing we all learned in kindergarten---do unto others!!