Measure first. Every case and frame decision depends on the footprint and height of the finished build plus clearance for lights or a stand, so begin with the size check guide and, for large builds, the set-specific guides for the UCS Millennium Falcon, Star Wars helmets and minifigure collections. Those show how to turn a build size into a case size before you look at any listing.
Next, choose the material and construction. The acrylic case versus glass cabinet guide compares cost per set and dust protection when you are housing one build or a whole collection, and the acrylic specs guide explains what panel thickness, base type and assembly style mean in practice so you can compare listings on the same terms.
Finish with placement. The sunlight, dust and cleaning guide covers where a finished set should live and how to keep the case and the bricks inside it clean. If you also plan to light the build, read the light kit hub alongside this one so cable routing and case openings are planned together rather than after the case arrives.