idk where to post this but anyway

My boyfriend's mom wants us to move into her house and we can buy it.. I see her intentions with this, as its fucking hard to even get a new place in the UK. she's with the council.. it's a 3 bed house and it really needs work. But the problem is, She says she is going to eventually move in with her boyfriend (they've been together like 14 years, but she's a major horder) so it hasn't happened.. What would you do ? I don't particularly wanna up and leave.. I think my bloke might actually be considering it.. he went though what he would do to the house etc -_- If you was asked and offered that, but with the unknown ahead. What would you do ??