hobby-go-lucky posted:Using catalogs as guides works, but sometimes product appearing in catalogs differs from the catalog specs and illustrations or is never manufactured.
I can't say for certain how good the more recent Greenberg price guides are in this regard, but they used to have an entry for not made (NM) or something like that. (though it's possible I'm thinking the terminology from when Tom McComas still did price guides - I'm pretty sure Greenberg has some sort of annotation for this)
It's a possible clue to help with that even if not always a 100% verification. It's better than guessing or asking 50 different people who may not remember whatever item you are interested in.
Been looking for a Lionel Steam Service Siding Accessory from I think 1998 for almost 20 years now. Also an Amtrak Talgo Train. 
(kidding - both are items that were never made)
-Dave
