How much are you willing to pay? I can see myself paying .99-$2 for gear used to level up to 60.
Once I get to level 60 I only really see myself paying $5-$10 for a piece of end game gear.
To be honest the only reason I see myself buying gear is to make farming the end game easier so I can get better gear faster. And buying gear for PVP.
Personally the appeal of the game is farming the gear. Once I gear out a character I normally play it for a bit then roll a different class.
How about you guys?