OP - We won't be building on the land until at least 2014. So next year's refinance is just for our current mortgage. We're hoping to get a second loan for the land, and then just sit on the land until we want to build. So in March next year, we will refinance current house and go for pre approval for land purchase.

If we move in with mum now, we will be selling our house now, buying our land now, but still not building until 2014. The deal with mum is that we have to live there until they return home in 2015. Does that make sense?