I personally could not be bothered moving if I knew that I would be moving again in 6 months. I hate the packing and unpacking. And it always costs money to move. But if you hate where you live now and your new surroundings would be lovelier for you and Bub then go ahead and do it. The pleasure you get from enjoying a nice home and environment would make it worthwhile. You'll just have to make sure you get an equal standard of living for when you move to Melbourne!