Can anyone direct me to a good plumber in Kunming?

That will be a tough one, I have had the plumbers round a few times in recent weeks, they say sorted one thing then another appears!!!

Frustration......

Try going and asking your building management. They usually have a guy that they use. Also they would not recommend someone bad, as it is there reputation.

When we moved in to our apartment we called the building management about getting a new kitchen faucet and drain installed. They sent one of their guys who was totally clueless and didn't have the proper tools.
Last year we replaced both faucet and drain (again) and had the man from the shop come to do the installation. He knew what he was doing. Caution though - that may not be true for all shops.