Sorry for that loss in information in your collection.  I will think about ways to migrate or notify users about these deletions so they at least know the item was deleted and can add all the details back to the correct item.  

Please describe more about how this feature would work/look on the site?  

I'm guessing something like this:

You would click "watch" button or link or something on any particular listing on the marketplace.

Then there would be a page showing all the items you have watched and their current status

You could remove items from the watch list from this page or from the listing details page too

This extension you describe already exists.  Any items in a wishlist that get listed on the marketplace at or below the market price, will generate an email notification to users.

Closing.  Fixed with alphabetical sorting.

This change is updated in code.  It will go live with the next server update, usually within about 24 hours.

Good suggestion and one that is very easy to change for list of games by console.  For example:

https://www.pricecharting.com/console/super-nintendo

Thanks for this indepth request.  I'll wait to see what other people think of this idea.  Most of these steps would require a very big redesign of the database or a big investment in processes.  

We already have processes in place to automatically flag outlier sales and we have people processes questionable sales all the time.  We are working on some data improvements for items with no clear indication if they have the box or manual based on the title of the ebay listing.

You can filter your collection to "Box Only" or "Item and Box" etc to find these items now.  Here is an example for my admin collection:

https://www.pricecharting.com/offers?status=collection&seller=dx2vp7qam7omfdwgu7jk6mw4f4&sort=starts&category=all&condition-id=8

You change the Filter by "Includes Only" to the value you want to see.  It doesn't include all of them at once, but it will show you only incomplete if you look at a couple different filters.

Closing as a duplicate issue.

https://pricecharting.userecho.com/communities/1/topics/950-add-apple-ii-games

Please vote for this existing issue instead.

We have those cards here:

https://www.pricecharting.com/search-products?type=prices&q=snowflake+pokemon

They were not part of their own set, but the cards were listed for other sets and had snowflakes on them so we list them as variants on the base cards.

Can you give me a link to a page on our site that has sales like that?  Or a screenshot?  I definitely want to look into that.  The only time I've seen sales like that is when they are really old sales (when the prices were much lower) and ebay doesn't keep listings on the site past 30-60 days or so.