Sell now or wait?

[outcast]

I have a big library of games and some of the games are valuable. I have been thinking of selling some of them, but I dont know if stuff is going to get even more valuable with time?

For example I have Resident Evil Gaiden for gameboy color. I have seen it go for 200-300 dollars on ebay. It would be a nice extra money to sell it off, but maybe it will be worth double that in 10 years?

I have no experience in this collection area at all really. Will rare games increase in value over time, or are the value static after a while?