My items on all my accounts are long-tail.
I don't expect any given item to sell within even a year.
However, my items are small enough that I can keep my entire stock, about 4000 items, in four bookshelves and a closet.
I use Promoted Listings at the minimum 2% on perhaps 15% of my listings.
These seem (and anecdote is not data) to bring in Views BUT they don't sell faster than non-PL items.
I think this means PL is bringing in eyeballs.
The sales however, which are higher since I started using PL, seem to come from Viewers who then look at my other listings (and I have a link to my Stores in the Description) and purchase those.
So I get the benefit of PL, more Views, without often paying the fee for the advertising.
That being said.
I do use Best Offer on all my listings.
I send Best Offer to many of the listings eBay suggests- but only if they have been in stock a long time.
- And I put Notes on my Active Listings page so I know when items were listed.
-Interestingly, although these Offers are lower than by own acceptable Best Offer, they sell better.
I list as often as possible. New listings definitely get more Views and more sales.
Most important.
Viewers view.
Watchers watch.
Buyers buy.
