"How much money" is the #1 question I see on the forums, Facebook, and email. Also, it's the #1 most difficult question to answer.
I've met "hippies" that were picking fruit, fishing, and getting by on $5 a day...or you can spend $100 per day. Depends on you, the destination, luck, your comfort, what you do, etc.
One thing is for sure, though: bring more money and less stuff with you on your trip!
Ever heard of the Law of Attraction? Celestine Prophecy? Google them. Call it esoteric, but holy s*$# they manifest themselves on the road. You actually attract success just by not assuming the worst. Just when you think you're broke and down to your last penny, an odd job falls into your lap, a rich guy hands you a $100 bill, or you find a fun gig to earn some cash.
It's not Hollywood -- amazing things actually happen.
The point is...stuff like that only happens when you keep your chin up and your eyes open. Vagabonds aren't vagrants. You won't end up sleeping on the street (unless you want to).