I will never understand why when you expect to sell a few hundred units of a product at most, you would decide to go and build something in china. There are instances where building in china might make sense. this is not one of them! you can easily hand assemble everything yourself in America, since this was a 1-year long time-frame. There is phenomenal CNC shops in the east coast (and also some in the mid-west) if you don't mind the lead times. You don't have to deal with tariffs, imports, and more importantly THEY SPEAK YOUR LANGUAGE. Yes this sounds dumb. Like, with Google Translate you shouldn't have a problem no? Think again! From my experience with Chinese metallurgic, they are clumsy and often mess up even straight forward designs. Yes, they are fast, but at what cost! They will redo it as many times as you need. But the headache, man the headache of dealing with it is not worth it. On the other hand some of the issues here are expected and fun! well maybe not fun, but part of the process, like the swapped components in the board. it happens to the best of us and that's okay! but it would always be easier to debug when you can drive yourself to the CNC factory, or at least have a video call with the tech in your own language. Also, regulations in china is whole different world and not at all straightforward to navigate for westerners, at all. I really don't like that people turn directly to china cause "that's what everyone does anyway". nu-uh. also, China is not the only option! Eastern Europe, such as Poland, can get you there too for reasonable prices, and have tons of phenomenal electronics and manufacturing engineers. Tons.