Cacti need good drainage and as long as they don't get too wet a lot of them can tolerate some cold. Freezing isn't good for some of those that originate in climates that don't have cold winters.
Here in the U.S. you can find a lot of pre-fab plastic greenhouses buildings. A friend has a very efficient one that he bought at Sam's Warehouse Club (a branch of Walmart) about 10 years ago for $1000. Shelves, countertops, good drainage areas, vented windows and roof to keep the temperatures the way he wants. It's quite durable and very attractive.
I have a 7' x 13' dog kennel (cyclone fencing) that, with a heavy plastic wrap and a lid of some sort, would work for a temporary greenhouse.