Foreign investment accountant needed!!

Hello everybody.
I have been living in the UK for the past 8 years and I managed to buy a house in north NSW which I have rented out to friends and a separate piece of land next to the house. I wanted to build a resort accommodation of some sort in the vacant land, but I’ve just found out that the council is not going to approve it and I therefore thought to sell up everything and buy somewhere else where I will be able to build a holiday resort or bed and breakfast. My big question is will I have to pay capital gain? On both the house and the land?If yes how much, considering that I haven’t been earning in Australia. Any help will be appreciated. Thanks