Budget as much as you can - Dam is a money pit! Much of this depends on your level of self control, but as you're going to be a toker in one of the MJ meccas, I think it's safe to assume that you'll have little self control and therefore little money!! :)
As a guide, top end gear costs 12-15 eu/gm and regular stuff around 5-8.
And a blowjob is about 50 eu....my mate told me....*cough*....i'm sure that's not massively high on your to-do list ;)
Accomodation can range from grim to great....depends on the time of year mainly. Cup time in Nov is mental, as is Queens Day in May. There's great places to stay for 100eu a night.....that'd be what I'd budget for accomodation. I've done the 40eu a night and it's just not worth it imho...(grim, lack of sleep etc)...or I'm just getting too old for the hostels....