Our build space at the time was housed in a tech training center at a local Community College. We would generate CAD files and they would print parts. They have training in Wind energy, Robotics, Police, Machine shops, to name a few.
As I recall it was very expensive to print. They had told us they had one cartridge that was about to expire and it could be used.
Yes the room had to be preheated.
I do not know what printers they actually have.
We do not build there now, but we still have access to printing through mentors that work there.