You can have a custom display case made for an item of this size, but it will run you a few hundred dollars. I was able to make mine for under $50. It's just not easy.
First, it's a large case. The dollhouse might be half inch scale, but to be able to cover the entire thing, will require a larger dust cover. For that reason, I decided to use thinner acrylic, that can be cut with scissors, instead of the usual thicker acrylic that has to be cut with a craft knife. The longer the cuts, the more difficult they are, so using scissors makes it much easier. Also, the larger the case, the heavier it will become, so using a thinner material allows the dust cover to remain light weight, hold together better and be easily lifted. For this reason, the acrylic at the hardware store was not an option, even though they can make these straight cuts for you.
It is difficult to tell if the poster frame, you are buying, has thin or thick acrylic until you remove it from the package. Your best bet for determining this is by where the product is located in the store. If you buy your poster frame in the housewares department, where the other frames are, it might have thick acrylic. If you buy it where the posters are, it most likely will be thin. The thinner the acrylic, the cheaper the poster frame.
To hold this thin acrylic together, I needed to make a frame. I painted wooden sticks white for this purpose. I then measured their height and glued them together in an L shape to create a corner. I then measured and cut the acrylic. The side edges do not have to be perfect, as they will be covered by the corner frames. I then sanded the edges, of the acrylic, a little in order to roughen them for better adhesion with glue. I glued them to the corner frames, until I made a four sided display box. I added an extra frame across the top edge for better stability and for holding the top cover in place.
I then measured and cut the top cover. The top cover is just placed along the top, horizontal frames and held in place with a small piece of clear packing tape at every side. The tape is practically invisible. This case is light enough to be easily lifted for access to the dollhouse interior and landscaping. This case is for keeping dust and hands out. It is not strong enough to protect the dollhouse for an impact.
Most dollhouses will not require a large, custom display case like this one, but the Fairfield's architectural structure makes it too difficult to apply dust covers to the back openings only. This dollhouse is also small enough to become very dusty on the exterior and on its landscaping, so covering the entire thing is more effective for keeping dust and hands out. Though making this case was very difficult and time consuming, it's worth it in the long run. My other dollhouses have back dust covers and they have remained dust free and their miniatures safe, for years now.
You can visit this dollhouse gallery here.
