Check the offer carefully - Air Hong Kong don't operate the A310, but do operate the A300-600 and a few Cathay B744 BCF s on lease.
Tax issues have been beaten to death on the FH forum, research a little, lest you are surely flamed for asking dumb questions. Short answer: if you're paid from HKG, expect to pay HKG tax.
You can live in HKG, but you're expected to live in SIN or KUL. Housing or housing allowances are not provided.
The answers you seek are here somewhere, try looking under a thread entitled something like "Air Hong Kong, the A300 outfit"