The stench of sewerage constantly pours out each plug hole in the bathroom and the toilet bowl.
The way we minimised this was to put a towel over the shower drain, keep the plug in the hand basin, put a bottle over the laundry basin (which is in the bathroom - but has no tap available to fill it) and keep the lid down on the toilet as much as possible.
We purchased a scented candle from the port fairy weekend outdoor market which we kept burning whilst we were on site.
Keeping the bathroom door shut was also helpful as the bathroom opens onto the lounge and is a few steps away from the kitchen.
As a side note, the stairs to the upstairs bedroom are so steep that they are ladder-like. The one toilet is downstairs.