I've sold a few on ebay, which to me is a whole lot better than sitting in a box in the attic. I didn't make anything like £200, but my models aren't a patch on yours Steve. Would you ever want a model back? Surely the fun is in making them, so if you ever wanted to make another dio with a base similar to this one, I bet you'd prefer to make a new one?
I agree with you about commission work. With my woodworking, I really enjoyed making things for myself and the family home, but when people started offering me money to make "one of those" for them, all the fun went out of it. (An exception was some filter baffles I used to make for a local factory - basically like a small pallet about a foot square. The fun part was that I was using scrap wood out of their skip, spending 30 minutes making each baffle, then selling it back to them for just over a tenner! This wasn't really woodwork though, just nailing bits together.)
Pete