My two cents? Only take over the unit if you really, really want to own it. You also said "[your] wife didn't pay the maintenance fees." Do you want it if it is behind on maintenance fees? Do you want to pay off those fees just so you can own it?
I would also be leery of paying fees on another person's unit. If you really, really want this unit, I would pay the proper transfer fees to transfer it into your name legally. But you also have to make sure that all the maintenance fees are up to date.
Lance C.