The first free houses should be in 10 days. Got a message 4 days ago that I will loose my private house in 15 days. So it should be between the 21rd and 24th.

Some ppl are waiting for the refund of the private house to transfer and cleaned the house 2-3 days after the patch. So maybe there will come other free plots after christmas eve too. You should have enough money to pay the full price for the house (12+ million Gil without discount for a small one, 40+ million for a medium if my memory is correct).