The amount of money I would carry would depend on how much I think I need to spend a day. It depends from person to person. Some people can't live without their latte while others like me never drink the stuff. I typically spend around $10-20/day but that's riding 100-125 miles a day on average. If I was only riding 50-60 miles a day I could more than likely get by on an entire year long trip for under $4K. For me my number one expense is food, accounts for roughly 75% or more of the money I normally spend. One the 1700 mile trip I did three years ago pretty much laundry and food was my only expenses for the trip. My food budget is higher than most because my caloric needs are much higher than most due to the high miles per day I ride. Like I said it wouldn't be that hard on a year long trip to spend under $4K and that would be riding 18K miles over the course of the year. I don't spend any money on camping/hotels and I don't spend money on trinkets.