I'm very happy with my Sunglo greenhouse. We ordered it as a kit and assembled it ourselves. The kit included necessary ventilation equipment. It also came with cedar shelves which can be removed. I use the shelves early in the season for flats. Early in the season, while flats are on the shelves, I bring the roses out of storage and put them on the ground under the shelves to get them started. Then I remove them when the flats and roses go outside and the tomatoes can be moved from the house to the greenhouse. The aluminum frames provide support for the tomatoes after the shelves are removed. I find using pots gives me the greatest flexibility.
I provide supplemental heat only in spring and fall for a few weeks. I close it down in the winter.
You can see the shelves stacked in the back of the greenhouse on the left side of the picture.
Click to enlarge:
