pylon:
Wrong, it's a good starting point for bargain hunters that don't care to throw the thing away if it doesn't work. Makers usually need at least a basic documentation but on ebay you usually get nothing. So in the end it's a good starting point for frustration and hassle. If you really know what you're doing and what exactly you need it's better to use AliExpress as there you have a higher chance to get in contact with the manufacturer which might provide some documents, even if they are in Chinese.
Well that's a learning... heard about AliExpress ( Jack Ma ??) . Willcheck out .
Thanks