Registering a company in HK is much cheaper than in China for foreigners.  However, as a Chinese national, registering a company in China is just about as cheap.

However, when you register a company in HK and have a representative office in mainland China, it is illegal for that office to generate profit.  It used to be very easy to work around this, but in the last few years they have really started to close that loophole.

The below is the info I've garnered from when I was looking at this, only a month or 2 ago...

Using an agent, about $2500USD (if I recall correctly...). But, there will be yearly expenses on top of that.

I can't say what the laws are like for Chinese, but for foreigners, it can be a way to move your money about more easily - profits, etc.

I've seen (advertised on the internet, so validity may be questionable) that local agents can register a business in China for less than 2000RMB.*

Representative Offices (RO's) aren't worth getting involved in (for a foreign company in China). Too many legal issues. However, there are other options available - Joint Ventures, or Wholly-Foreign Owned Enterprises. Your foreign owned company (eg, HK registered company) can own these... (instead of an individual person). And, there are various breaks the Chinese government will give (such as tax breaks, etc).

As for 'running' - yeah, easy! Well, you do almost nothing.. except when it comes time to hand over the accounts to the HK govt. Even then, part of the deal often includes having those statements drawn up, etc.

(Just make sure you've got a HK bank account as well.. makes things much easier with money transfers).

(*- that 2000RMB or so does not include required starting capital... which starts about 100,000RMB - of which you need to deposit about 20% of that into the bank fairly quickly (but you do have a couple of months...), and the rest within a certain timeframe). IIRC, initial capital required for a HK company was.... $1

yes it is very easy to register..