Forget HKG unless you make 100,000hk/month minimum. The cost of living is at least 150% higher than just about any other city in the world.
Better off going to mainland china where you make double what HKE makes and the cost of living is a third.
70,000/month is NOT enough. I know, been in HKG 5 years, have seen prices of everything rise between 4-7% a year.
My rent when I first arrived was 14,000. Withing 1 year the owner raised it to 18,000. Two years later she sold it and the new owners rented it for 28,000.
Don't even get me started on food, restaurants and alcohol.