The three factors you mention -- "increased immigration", "shortage of land", and "shortage of construction labor" -- to the extent they exist, mean that there will be increased demand and reduced supply of housing. All else being equal, you'd therefore expect that the market-clearing price will rise. For instance, it might rise so much that emigrating to Australia becomes less attractive, or so that wages in construction rise and more people are drawn into working in construction.
(I'll note in passing that the third point seems to somewhat contradict the first: in many countries construction jobs are exactly the sort of job that new immigrants can do well, but it's possible Australia gets the wrong kind of immigrants, or unions restrict access to these jobs, etc...)
However to the extent these factors are true, you would expect them to drive up both rents and sale prices. But it seems that sale prices are rising considerably faster than rents.