I have so many items. It varies. Some hot sellers move within 12 hours of listing, while most take a week or two. For an example of fast movers, 3 things I listed in the middle of the night sold within 4 hours while I was sleeping.

The things I price high or are super uncommon/rare (waiting for the rare buyer to come along) can take a few months, or even a year+. I try to keep those items smaller in size to manage my space here. If something takes too long to sell, I'll discount the price or take it apart into smaller pieces to save room.