Well we wouldn't be in the UK until January next year (travelling central Europe between October-December) so will be interesting to see how the 'Brexit' unfolds.. I couldn't imagine the benefits of leaving the EU would outweigh the advantages? But this is from a very remote point of view and not sure of the finer details so won't add in my 2 bob.
Average house prices in Sydney are now >$1M (AU) so pretty comparable with London by the looks of it. We will be renting our house out here (Wollongong, an hour south of Sydney) and just renting wherever we reside in England so not too worried about the cost of buying a house over there at this stage.
Come oop North, the weather is just like in Australia bar the rain, misty rain, cold rain, snowy rain, vertically rain, wet rain, heavy rain, it will be just like home :)