If you are in the process of designing or purchasing a greenhouse you probably have questions about what accessories you should purchase with the greenhouse. I get asked this a lot. Some people want to completely ignore the accessories, while others have read every article and believe they should buy everything that you can put in a greenhouse. My recommendation is to start with the ventilation package. Yes, you will need it even if you are only overwintering plants and even if you are in a cold location. I have seen sunny winter days when it was 60 degrees outside and my fan and shutters were operating. And, I keep my ventilation system set at 90 degrees. On the other hand, I hate to see people load up on a lot of items that they will never use. A heater is a good idea, if it is close to the time of year you will need it, or if any modifications to the structure are needed to accommodate for vents, etc. I think the rest of the items should be added as needed.
Here is a nice article from our friends at Garden and Greenhouse which talks about some small hand tools and re purposed items. These are things probably most of us would never think about, but will be used over and over again.
If you already have or are thinking about getting a greenhouse you should consider purchasing several inexpensive tools and related products. Although the items are not very expensive they can make a difference in how much you enjoy greenhouse gardening and how efficient you are at doing it.