I don't understand the request.  Can you give me more information about what this means?

You can sell Pokemon cards here.  

https://www.pricecharting.com/sell

You can export a collection now.

https://www.pricecharting.com/export-collection

The link for this is in the settings page.

Let me make sure I understand.  A user wants Mario Kart 64.  They don't see any for sale in the marketplace.  They can then find other collectors who have that item in their collection and make them an offer.  If the owner accepted then a sale could be created on the site between the buyer and seller?

What do you mean by viewing your cards in different ways?

This is a duplicate of this request.

https://pricecharting.userecho.com/en/communities/1/topics/1226-can-you-please-add-the-famous-sharp-x68000-to-the-list-of-console

Please vote for that request so we can prioritize.

Please give me a link to these other guides online and I will add them too.

If you can give me a link to a few of these sales then I can edit them and see if we can fix the issue.  If Goodwill doesn't say what is included in their listing title, then we won't be able to make a general rule to fix all of these.

Because these consoles play multiple cartridges we do not have a place to put them on the site.  Every item has to be linked to a specific console.  So we cannot add these at this time.  Sorry.