not to sound snotty but im probably the best person to ask...
i hit 15 countrys in 3 months
it only costed me 3 G's (not including airfare. im not gonna spend years explaining everything ill just give u some basics....
stay in hostels. fuck that movie bullshit that scared every one in the u.s. shitless. hostels are the shit. all u do is party and meet people just like u and go out clubbing with them. including fine ass bitches.
vienna sucks balls. its a retirement city. its not fun.
make sure u stay on RAMBLAS street in barcelona. that street is crackin till 8 am every night and its neer the beach and theres a legal wall near by including a piant store that carries non stop spanish montana (its made in spain so they got that shit on lock yadadaholla)
go to copenhagen in denmark and hit up the town called christiania. trust me its a hippy colony that has weed plants growing from the street cracks (litteraly growing like weeds everywhere) plus legal walls up the ying yang.
fuck a hooker in amsterdam. once again u gotta trust me buddy.
as for places to avoid......i dunno i didnt like milan, in italy, u mentioned zurich, its tight......but its outragiously expensive. i dunno on this subject just pm me dude i went way too many places to name shit off the top of my head.
dude just fuckin pm me.