http://www.demo-it.net/demo-games-for-ps1/

Future value of some PS1 games?
I've been thinking about selling some of my old PS1 games, and I wonder if anyone knows if it is worth a few the worth selling now or exploitation by a few years (ie, it is likely that its value could increase, I'm not talking a lot?), or if it is not worth sell everything? (Unless otherwise noted are the original, platinum and all are in good condition) a Metal Gear Solid (inc. demo silent hill and the station 7 demo) MGS Special Missions X-com enemy unknown Streetfighter Wipeout 3 Special Edition War Pigs collection of White Point 1 and 2 Silent Hill
I think, as all very old game, which will increase over time if they are still in good condition when it comes to selling. I have only about 30 PS1 games that just play more. I'm just going out for a few years so I can get some money for them! Hope this helps you, Nat:)
Old Playstation (PS1) Games