Expect low pay as these sort of drivers are only there for the hours. DHC8 Captain with good PNG experience should be on a decent package. Ask if the exchange rate Kina/AUD is guaranteed by the company ie. if the Kina falls below X to the $, the company makes up the difference.
Living conditions, depends where you are. Moresby/Lae unpleasant and very dangerous, Madang nicer.