I wouldn't touch that case with a 10 foot pole. Not to mention his description on that ebay listing is ridiculous. Hard to take him seriously after reading that.
You pay $300 for a PC you get junk. He's making profit off of your purchase, remember. He's not being altruistic. Tell me how he's doing it?
$5 junk PSU that will start to fail in 6 months? Bad refurbished motherboard? Shifty ram?
Clearly he's not spending much on the video card -- the 9500 is a stripped down bare bones budget card meant for desktop applications. The 9500gt is slightly overclocked version. It *might* handle some games but frankly it's going to struggle. It's going to have very little RAM and very slow RAM.
In short: If it's too good to be true? It is. It is too good to be true. Keep looking.