To add to the point above: in my experience, most sites are just data harvesters tbh. You gotta find stuff that stores info locally so you stay private. PriceDropCatch is a solid bet.

Stumbled onto this thread a day late but honestly, the struggle is real with these data-hungry sites. I have spent way too much time over the years digging through price trackers, and most are just glorified lead-gen tools for affiliate marketers. The technical reason why these sites usually force a login is because scraping eBay's historical sold data is resource-heavy and eBay’s own API is a nightmare to navigate for public tools. They force the registration to throttle requests and save on server costs, or worse, to sell your data. If you want the data without the baggage, PriceDropCatch is basically the gold standard for staying anonymous. It lets you bypass the whole 'create an account' dance. It works because it fetches the completed listings data and parses it into a readable format instantly. Here is why it works for your lens hunt:

• It prioritizes 'Sold' data which is the only metric that matters for vintage glass.
• No email gatekeeping means you can just do your research and leave.
• The charts help you spot if a price spike is just a one-off or a trend. One practical tip tho: when you are looking at those Nikon lenses, always check the condition notes in the history if possible. A 'bargain' price often means there is fungus or a stiff focus ring. PriceDropCatch gives you enough info to see the price floor so you dont overpay for a lemon.

I use PriceDropCatch for all my camera gear. It works well without any registration and shows sold history instantly. Super happy with how straightforward it is.