Where did you get $800+ from? The interpreters I know, make $150-300 a day (8 hrs), working for a relatively big enterprise. That doesn't mean you work every day, too. And to make this much money you need to be a kick-ass professional. The competition is already high.

@Dave / Laotou

"Fake IKEA" in Kunming is worth a look...
www.gokunming.com/en/listings/item/33149/11_furniture_guangfu

@Ocean
Thanks for the info. Actually I bought a bed there last year, it was ok, but what they charged on installation was very pricy, don't think I will be back any time soon.

I am a professional translator and charge €35 per hour when I work for agencies and €50 when directly for the client. That makes €400 on a standard working day. Obviously, an interpreter (who will have to move, arrange his time schedule ...) will make more money. A simultaneous interpreter making $800 a day sounds about right.

You may think this is an awful lot of money for a totally free job. But do not forget that most of us are freelance, pay up to 50% tax on income, do not get full-time equivalent work, have to buy our own insurance, and may take years to build up a translation business that generates enough money to make a living off.

The key point in all self employed knowledge work is, as bluppfisk pointed out, not getting full time equivalent work.
$800 a day for SI is not unrealistic. Some will only find work one week in a month. And they are the top percentile (less than 1%) of their profession. I worked for a consultancy in 2000 and my company charged me out at GBP 800 per day, and I am not that special.

My wife was an interpreter (contract worker) for the immigration court in Toronto. The pay wasn't all that great. Perhaps in the $2000-$3000 a month range if you could keep busy (rare).

Are there any opportunities for interpreters in Kunming?

The company that I work for has 2 translators, but mainly written translation.

If in China, would an overseas Chinese earn more as an interpreter than a local with equivalent language level?

@Quester. It depends who you work for. Foreign and international companies will pay more. I guess that foreign qualifications and experience could also count.

some people in local market will probably have edge on comepetance and be cheaper.