How do I easily check the market value of various items, especially collectibles (like stamps and rare coins)?
I can't find a single, proper price with Google. There are lots of prices, and a huge price range. Isn't there some platform to find market prices easily?
Auction sites obviously. Being knowledgable about the items in general (and their significans to their respective cultures) will make estimating prices easier to.
If we are talking antiques go to a professional firm and get it valued by them. And make sure it is going on an auction afterwards, so the company doesn't just take your shit.
Back in the 90s they used to publush books listing average going prices for these things. My coin shop had several.
Problem is the demand for such things fluctuates widely and prices are very volatile. So it's hard to get a definitive price on what something is worth. Basically, it's worth what someone feels like paying g9r it at that particular time.