Market

Hello

Is there anywhere I can read about what the market feature does. Some how to guides would really be useful. I have a ton of questions about this feature.

Am I right in thinking customers can have their own store? What can they sell? is it digital or real items? If digital such as a clip or image, I can not see a way for a buyer to buy and receive instantly, you can upload a video or picture but the buyer would of already seen it, is it a case that if selling a digital file it would be manually forwarded on or posted if an actual item?

How does the payment work for the sellers, does it go straight to the buyer? if so do they need to set up business accounts and enter API keys ect.. 

I am also interested in reading about the messenger app. I have read somewhere group calls can happen in chat boxes? Again I have a whole list of questions on this one about the video function in the app. 

There should be a user guide or manual with all these apps and mods, yes some are self explanatory but some its a case of messing around trying to figure out all the uses. It wastes so much time, just having something to read about them would make life so much easier.