Thanks everyone for your input.
My thinking was not as much for buying/fixing/selling, as it was for just ensuring that if I make it pretty again, that it will sell better eventually. I'm not meaning for this to be like "flipping houses" kind of thing.
My intent is that I buy something I really like, fix it up into something I really love, use it awhile (or for years and years) and then when I die, my kids/grandkids have something that is not just "antique" but actually works, is usable, and is pretty too!!
I'm thinking seriously of taking a class to learn how to fix up the older machines, but not the newer computerized ones - those would be pretty much "manufacturer/dealer dependent" anyway.
Again, thank you all for your input.