I have a three ring binder. It's got categories (sanding, polishing, carving, etching, granite, drill,. . . .).
I cut photos from catalogs and glue stick them in so wifey has a clue as to what they went for new.
I have some notes to remind her some items may take a month of Sunday's to peddle, but, the shop space is doing nothing anyway.
The main thing is to make sure asshats that like to play the "I'll give you twenty for that [Festool] sander don't pull it off. And, of course, those CBN wheels on the variable speed, four wheel grinder weren't free, but who, aside from us, would know?