Featured Spent the day listing postcards on the 'bay.

They are luckily pretty easy to research/look up. I’m sure you know already but some things to look for are RPPC, sports theme, disaster theme, anything racy, California cards, military, and transportation related cards all do well relatively speaking. Anytime I’m trying to get a feel for prices in a new niche I just search the subject on eBay and filter for sold results, sorted by highest price. Search “postcard” and just scroll through the top 500-1000 results or as many as you can stand. That will give you an idea of what’s great and what’s not. Then I do the same thing but for a category like postcards I’ll search for sold listings at like $20-$50 or so. Unless you have a curated collection you are unlikely to have big money cards but the secondary eBay search will give you an idea of cards that have moderate value and may be worth pulling and selling separately. Or if you’re doing auctions I guess you just let the market tell you what’s what. American cards are usually better than European cards. Older Asian cards are usually good too. I’m probably not telling you anything you don’t know already but best said just in case I am.