I do appreciate your frustration, I've felt the same on occasion.

But my point was that ebay (the auctioneer) shouldn't be giving the bad advice that "start your auctions at a low price" is these days.  The results are reasonably predictable and far more so than in the past when there were more collectors than dealers competing for the same items.

A very quick check of the last 10 items in the Saved Search I mentioned earlier shows that  7 out of 10 sold for the opening bid, only 3 achieved multiple bids.  5 of the 7 were sold by private sellers (judging by the 'odd' start price with odd pennies indicating the BPF(?)).  All of the 7 achieved less than I'd expect for the item, as did 2 more even though they got multiple bids.  So 9 out of 10 auctions under-achieved IMO, compared to BIN listings.

For example a popular and collectable glass clock  - 1 bid  = £4.35  (usually goes at around £40 - £60)

A popular centerpiece bowl  - 1 bid = £0.08p (usually £20 -£30)

A pair of candlesticks  -  4 bids = £4.35 (usually £10 - £12.)

I do accept that there are lens tools and other research that sellers should do or suffer the consequences.  But when I use lens tools for researching glass I find they have been prone to being US centric and although I may be researching a piece that I'm 99% sure is of either UK or European origin, the 'similar' pieces the lens search gives as results are quickly filled with US and all too often modern, not vintage and not European and not much help.

Even researching prices for glass on ebay is not as helpful as it once was, because the variety especially in better quality items has declined as better sellers have largely deserted ebay and sell elsewhere.  Probably because of the consistently poor prices achieved here, now.

When I'm researching prices these days I look at what is on offer and recently sold on ebay, but to get a better idea and realistic pricing I also look at etsy and google shopping.