I worked in a small foreign office in Beijing, with a local LAN, half a dozen pcs with English Windows. They were Acer I think, we bought them from an Acer sales rep and he helped install them as part of the deal (not the LAN, not sure how that was set up). But any problems, we’d phone him and he would come to the office and fix it, whether a overheating fan, driver update, graphics card, etc. His call out charge was ¥100 so just parts on top which he sourced from his local shop at honest prices (although I expect he made a little on them as well). He would often lend us a part, fix the other card or what have you and bring it back a few days later.
Sometimes I wished he would use more genuine parts, or know his way around the system in English a little better, not install extra software in Chinese on the hard-driver, or ghost partitions, but for the price we paid, the system was always working and no complaints. I guess he had a regular salary / commission from the pc store he worked at and so these occasional calls were a little buckshee for his cigarette habit, or what have you.
I think if you were in Beijing and could source the parts so quickly and were two or three times the price of our Chinese friend then our little office would have been happy to know about you. But probably not the Chinese secretary who liked to control the petty cash and ensure we always had a bargain. She never understood ‘you get what you pay for’ mentality. And even then you would probably still be struggling to make ends meet.
I suggest you try to upsell yourself to an IT company, whether foreign or local. Somebody like Candis (http://www.candis.com.cn/) or a Chengdu equivalent) that use foreign staff to help their image and increase their prices.