What i regret the most was when I had to sell my A4000 in MicroniK ISA tower with CS060 MK1 and CV64 back 5 years ago or so. Basicly I didn't have a roof over my head the next month if I didn't do something so did something drastic... sold the computer and invested the money in materials to restore a house.
If I didn't need the $ and it wasn't for the fact that I never used the machines and they took up too much space I would probably not have sold my 2 A2000, 2 A3000 and 2 A4000 but there's just so many machines that one can use at any given time. :-D