Do cheap greenhouses work?
There might be fewer extras, like shelves, ventilation, or reinforced doors, but that’s not to say they can’t work. For a small garden or a beginner gardener, a cheap greenhouse can still do the job. Just know what you’re getting: it’s practical, but it comes with limits. It’s definitely possible to grow without heat if you use cold frames and/or hoop tunnels inside the greenhouse. In my climate, venting the heat on sunny days would be essential, even on cold days. Imagine a car parked in the sun all day.