Remix of wytewydow's diecast garage. The mechanism for the door operation is clever and I had a compulsion to take this a little further. I envisioned a design that appeared to have been built from 1920-70's and works as a display for diecast cars. Thanks for the inspiration!

Improvements:
Door fit; closure is much tighter. There's a tiny handle to pull the closed door open near the bottom. The door rails will need to be flexed slightly when inserting the doors the first time...they are designed with this in mind and you can take them apart again and again.
All parts are now printed separately and assembled to reduce plastic waste. Most don't require support.
This is a bigger garage, holds much larger 1/64 scale cars with extra space for other garage stuff. Delivery vans fit.
Better visual access...you can peer in from all four sides and the roof through interesting windows. I tried to leave surfaces smooth to accept "glass" by scratch-builders wanting dirty or cracked window panes.
Adds a drive-way that seamlessly extends the garage floor outward and has a little dip to hold the cars in the right place when parked out front. You can drive your cars right out of the garage and onto the surface below fairly smoothly.
All walls/floors/roof connect via a tongue and groove and are locked together using straightened paperclips (5 small paperclips). I used a 0.5mm drill bit to clean-up the paths for the paper clips so that they slid in and out easily. I just turned the bit by hand, don't use highspeed unless you want to mangle things. Bend little 90 degree hooks onto the ends of the vertical paper clips(4) so that you can fish them out later, there are little pockets for the hooks to sit when viewed from the bottom. The horizonal paperclip that ties the front/floor/driveway(1) gets no-bends and should be installed first and pushed in deep so that it doesn't block the vertical pin's installation...use an extra paper clip to set it in deep or push even further to remove.

Enjoy displaying your diecast cars. I'd love to see people do some painting and scratch-building using this as a foundation.

I had fun designing this and will make new versions soon. Adding some LED lighting and more interesting walls/floors/rooves to swap-out.

2023 UPDATE - Recently migrated CAD systems, will be making some new variants of this soon. LED lighting is the top of my list, let me know if you have any suggestions or issues with assembly clearance.