Yes, I have had 6 Pro outdoor cameras and 4 indoor cameras running on it for 2 years. Just pay attention to the signal strength. Just test it before buying an additional camera.

I too would recommend taking more bases for better coverage. In this case I would buy 2 sets of 3 chambers + kit

Yes, this is no problem and works well. Only the range of the WLAN limits the possibilities beyond a certain point. The more direct and closer the contact to the base station, the more secure the connection and thus the image transmission.

Yes, up to 16 cameras. Have fun