It all depends on what you do on the road and where you stay. I copied this from a blog where I had posted it before on a discussion of costs. ( Not sure of the forum rules here for links to blogs so I copied my part of the remarks.) The travel is for my wife and I, and we are Canadian, thus buy medical travel insurance for the states. These costs are from last winters trip to the much nicer weather of the southern states.
The Class C towing a Chevy Cobalt went 7733 Miles, used 1034.43 US Gallons, ($3475.71 at a calculated Average of $3.36 a gallon) I can then further determine that I get 7.48 MPG Avg. Accommodation Costs were $2590 for 160 days so 159 overnights for a 16.29 Avg overnight cost. We do boondock quite a bit thus the overnite stay average is lower then the $30-$40 a nite that is average for an RV park. I also use PA for discounts at parks.
From my US $ Mastercard I derived the following. Spent $2849 at Walmarts, $1232 at Grocery Stores(Albertsons, VONs, Bashas...) and $98 at Liquor Stores. The total for Groceries,incidentals, wine, beer and liquor would then be $4179. Eating outside of the RV showed $1096, while entertainment totaled $746. Spent $866 on gas for the car, $73 for propane, and Cell phone and Internet was $539.12.
Our travel Medical Insurance was $1305. I buy additional on top of my Mastercard yearly plan (first 30 free- for my wife who is still under 60), while mine is through Medipac where additional is purchased for the first 40 days (pension coverage) then full for the remaining 120.
So our total would be $14,869 or about $92.93 per day. Of course I did not include Casino gambling in the entertainment, which I purchase with cash. I replaced my RV tires this past year for $1400 and had a full brake job on the Cobalt for $642.
Hope this helps you. I certainly do not think my wife and I are monetary rich. We very much enjoy our time in the States during the winter, away from our house and the miserable weather we leave behind. The enjoyment of the time and the people we meet certainly enriches our lives.