I have no clue about insulation. I would like this shop to be insulated, but do not own and am wondering if there is anything relatively cheap and easy and preferably temporary that I can do to achieve this?

Can you give us a clue as to the purpose, construction, and location of the building?

The solutions that make sense may be different if it's a metal building used for fabricating ceramics in Tijuana vs. a concrete block structure in Whitehorse used for retail snowmobile sales, vs. a wood framed auto repair shop in Knoxville, vs. a plank clad pole building used as a farm-utility shop in Boise.