In the past 2 years some games went up some 100% or more in price. I bought a game 6 months ago for $90 I see listings for it on ebay for $150. Its pretty insane.
The real market value of games is seen in the auctions and Facebook retro groups (literally the only reason I have a Facebook account is for collecting retro computer parts and games. If you find the right group you can get some pretty good deals).
There's nothing wrong with quoting ebay, I use it all the time myself. Just don't pay any attention items listed with a Buy It Now price because they're often full of chancers. Just because it's listed at a price it doesn't mean anyone will pay it.
What you did is a common trap that new reporters do when they talk about how expensive collecting is. They run headlines like "your old junk could be a gold mine" but pad their articles out with hugely speculative Buy It Now prices that no sane person would actually pay.
> The games I want aren't available on facebook
Which games? I collect for basically every platform across basically every genre and I've never had an issue getting obscure games from Facebook. I might be able to help you out here.