Some items, like books, are 'long tail'. I sold a book yesterday that I had listed since 2014.
Look back at your Sold listings (Paypal may be easier than eBay for this.).
Which ones were most profitable?
Which ones are most replaceable?
There is the 'garage sale' seller and there is the specialist.
On this ID I sell mostly stamps for philatelists. I have a good describer of these and they sell slowly but profitably.
On another I sell sewing patterns. They don't take much room ( a hundred will fit into a banker's box) and they are steady sellers. I know now which brands and which sizes sell best (cheongsams and maternity wedding gowns) .
On yet another I have my garage sale. Mostly thrifted weird stuff sold for the fun of it. (Weird Al Jankovic grade).
Sell what you know, know what you sell.
Garage sale season is coming to an end, time to get thrifting.
