The types of games I enjoy seem like they never drop in price, and then go out of print, and just increase in value on the second hand market. I've also made some money this way, selling things like Suikoden 2 mint condition with case+booklet, etc.
I had to have my local gamestop call another gamestop to get me a copy of Xenoblade (the first one on old wii). It was a used game and I still paid 35 bucks for it second hand. It also said "not available online"
About a month later, there was a big article about how gamestop now considered that game a collector item and was selling them new or used for $125 a piece (which outraged a lot of people, accusing gamestop of price gouging among other things.) So I was glad to have gotten the game when I did.
There's lots of other examples.
My local gamestop usually gets between 0-3 physical copies of lesser known JRPG games. Because of this, I often DO preorder, so I can rest assured they will get me one on day one. I also sometimes preorder online via amazon and other sites.
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Of course, as others have said, it totally depends on the game too. My steam "wishlist" has over 250 games on it, but I wouldn't pay over $20 for about 95% of my list, while other ones, I will buy as soon as I have the extra funds (such as Witcher 3 which was also mentioned above. I want that game bad
. )
It also depends on what other games I currently have to play. I have lots that I need to finish still, which can sometimes help me wait for a sale.
But if I really love a franchise, such as Persona for example, I will buy the game on day one, or preorder it, always.
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