Transmog collectors want certain grey and the sell for thousands on the AH, such as these: https://www.youtube.com/watch?v=LHakjaXp4us
(Maybe also, find one of those AH statistical sites, and grab a list of their top grey items.)
The addon should keep a static list of these and make sure to avoid selling them, and notify you in the chat window that that item is worth selling on the AH.
Transmog collectors want certain grey and the sell for thousands on the AH, such as these: https://www.youtube.com/watch?v=LHakjaXp4us
(Maybe also, find one of those AH statistical sites, and grab a list of their top grey items.)
The addon should keep a static list of these and make sure to avoid selling them, and notify you in the chat window that that item is worth selling on the AH.