For starters I think some people should sort out and seperate all these lighthouses, by style. This would only have to be done once and it would be good way to see exactly what is there! Make a list and go from there. Delete them as they get sold. from now on you know what you have. It's really very simple.
How many pc's are we talking here? Does anyone have a rough idea?
Then people could see the list and request which ones they want to buy.