It's not my place mate but if you are that concerned about your potential mortgage then imvho you should not go ahead with it or at least give it more thought! House prices may only go up next year at about 3% on average but could easily go the other way and having such a big debt on your back can affect a lot of things that you may want to do later on.
Sorry for the lecture.
....anyway you can't sell BVC it's a winner and will enable you to pay down some debt plus I am sure you would be missed on this BB ;)