We used to have a timeshare in St Maarten that we really enjoyed, but it became a cautionary tale of what can happen. We purchased resale (as one should), so our initial costs weren't too terrible. At the time, the property was a fixed week timeshare operated by Sunterra. Things went great for a few years. First, Sunterra tried to convert many of the fixed week owners to a point system. Some did convert, but many did not (we didn't, we kept our fixed week). Then, Sunterra got bought out by Diamond Resorts and the maintenance fee increases began. In essence, our MF doubled over the span of a few years and we were due to pay more in MF than what it would cost just to rent a week. So, since no one would by our week (quite honestly, we didn't pay that much for it in the first place), we paid a paltry sum to Diamond just to get rid of it.
Eventually, the property was taken over by Hilton, so I'm sure it's much better now, and actually, I'd love to go back, just as a renter, not an owner...