asset library!
currently the "Food" category in my asset library has 82 items, but I probably have some more foods that haven't made their way in there yet!
I began using the asset library feature in Blender at the start of 2022, and usually when I make new props that can be used more than once, I'll put em in the library. There's still loads of props hanging out in other blend files that I've yet to stuff in the library, but the library is growing slowly!

As for character models, they are just stored in folders1. Blend files for renders are usually stored in the folder of the (most prominently) featured character model, but not always. Hell, the blend file for contactless delivery is stored in the asset staging folder, because I originally intended to just model the mousetrap and plop it in the asset library, but then I constructed the scene in the same file...
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Except the generic furries, those exist in their own asset library

