Comment:

Buying: Money!
Selling: DS/GBA

Practices:
Money always comes first. I read comment pages around here for a while and that's really what everyone else is saying and it makes sense.

[Kenzya] has more feedback than [User] - [User] sends first.
[Kenzya] has less feedback than [User] - [Kenzya] sends first.
[Kenzya] has around the same amount of feedback as [User] - Both send at the same time.

Prior Feedback:
I'm not new to the whole "internets" scene.
Ebay: http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeed...
DigitalPress: http://www.digitpress.com/forum/viewtopic.php?t=89...
GameTZ: http://gametz.com/usertab/Kenzya/tab/Ratings.html