What could be the reason that Blender won't save a model's scale. Every time I scale and save a particular model, then re-open it, it jumps back to it's original scale. Feel like I might have accidentally enabled something that I shouldn't have.
If you have set keyframes then keyframes will supersede a temporary scale action. Test the results when you scale and set a keyframe.
You can test by moving the frame position back and forth and verifying your intentions have been recorded.
If you have any keyframes then a scale operation may just a temporary exploration. Keyframes have CRUD abilities... for the operations of Create Read Update and Delete.