Are you Chinese, do you speak Chinese, or do you have a very competent translator? That is the first step in getting deals in China. The hotel-based and other more well-known tailors who do competent work may be equipped to deal with English speakers, but they will certainly not be under 100 dollars. You can certainly get suits made for 50 dollars or less even, but the best is for you to have a model for them to copy. If you want something that is really custom-made, approaching bespoke, you are going to need to be extremely persistent, demanding, and detail-conscious. Even skilled tailors will sacrifice quality in order to save a few dimes. And they will sacrifice it in places you may not be able to notice right away. You need to be sure about button holes (good buttons themselves), that they use good thread, not to mention the interfacing-which is going to be a hard thing to get across. I never figured out how to explain fusing/canvassing effectively, so what I had made is fused. You can go to the fabric market (mianliao shichang) of which there are two in Beijing, select your own a fabric and find a tailor there. Just ask a cab driver to take you to the city's largest fabric market. This is the cheapest method. I would certainly recommend getting something made there, but mainly for the experience. It will be a side of China, you haven't seen before. Look at what you get as a very personalized piece - stick in a crazy silk lining - and not necessarily brioni quality. That is unless you want to use a tailor that caters to foreigners and tourists. In that case you should be able to get something decent, for about 200-500 dollars. Even in this case, you better be insistent about what you want. Make a list with numerous points. You can get all of these from reading this forum. Anything you don't mention, they will fuck up.
So true. Chinese businessmen (tailors included) are born hustlers, it seems (btw, I'm of Chinese origin, speak reasonable Cantonese, and most of my mom's family are Hong Kong bred and born, so this is from experience, not prejudice). I used to think that I'm pretty savvy and not at all embarassed as most westerners would be. But without my cousins, uncles, etc... who grew up and live in these places, I would be taken to lunch. And be forced to splurge for coffee and desert afterwards