We own a house in London but are going to move out of London for quite a specific reason and period of time (10 years). I'm afraid if we sell our house we will never be able to afford to move back in. It turns out the house is worth quite a bit more as a rental than I realised. It would pay its own small mortgage plus management fees etc with a good chunk left over. Could we remortgage our current house and take some equity out and use it as a down payment for a another house? The current house could easily service the increased mortgage. Is this mad? Could it work?