I can see some problems down the track...
What if you want to spend money on your house, either renovating or "backyard blitzing" the place...because the bank owns half, do they pitch in?
And if you have "done up" the place on your own, what happens when you sell...does the bank still get half, even if they didn't cough up for the reno's?
Something to think about.
Cheers!
