I’ve done this. I took a while picking a projector as there seems to be various different specs that are quite similar. I decided to get one that could be charged by a power bank and it works really well. I also wanted one that had its own operating system so it doesn’t have to have something connected to it. I went with this one (though from a different seller)
Projector and have been really impressed with it. It’s tiny. It’s not particularly loud but works great with a Bluetooth speaker.
I looked at mounts and in the end went with one for a small security camera as they seemed much smaller then the actual projector ones which all seemed to have a big drop.
Mount
for the screen I just got a spare bit of curtain lining and used a plastic rod at the top and bottom with a couple of velcro straps to strap to the inside op the pop top (where the straps go to close it). It all works very well and can easily remove the projector and use at home too. The kids love it ...
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