I've been posted in Beijing for 5 years, earning a Shanghai salary, which is really nice. The cost of living here is quite comfortable for me. I'm a homebody, so I don't really mind not going out much – online shopping solves everything. No need to worry about mold, and there's heating in winter. The only downside to Beijing for me is probably the lack of delicious food. Takeout is often bad, many restaurants are meh, dessert shops are pitifully few, the crayfish isn't good, and the BBQ is overwhelmingly salty. Luckily, mutton hot pot is there to save my life!