Utahtea: We have been keeping these kinds of records almost since day 1. The first four years we only recored gas costs/miles/mpg, but then after that we have everything for the last 28 years! I keep little note books and made a spread sheet.
Last year we did 2,085.60 miles in the motorhome and spent 11 nights out on the road. (One of our shorter vacations!)
Our cost (averages, per day):
Camping fees: $19.77
Other costs: $24.47 (National Park Pass, propane, lots of souveniors)
Overall total (average) per day $106.35