Help with buying

[Reis]

I'm dying to get my hands on the older generation of Pokemon games, and so far the only one I haven't done is gen 4, however HG/SS Goes for $300 and Platinum goes for $40 on Amazon
I checked Ebay and the go for only $20, but i'm not sure how reliable they are, does anyone know if I should just give up $40 or hope that I get a copy on Ebay that isn't broken?

[Arctero]

You can check the reliability and the ratings of the seller on eBay. it should also say if the seller has a return policy as well. I would say go to eBay, or find a store like Gamestop that sells used games for a decent price.

[Reis]

I'm getting Soul Silver next week :D