I buy machines that expand the range of what I can present in the shows we do. Pre-1900 machines are exciting for me because of all of the attempts at various technologies. some worked, some did not. Seeing the gradual tapering of the myriad of designs to basically 3 or 4 "systems" that we still use today is, for me, the coolest part. Each machine has a place in the show. At this point I am "one in, on out" regarding space. Each machine is stored in a position where it can be used, so when the 1864 Singer Letter A with MOP came available, I sold my Florence Plain leg treadle to make room.