Wendy, pardon me for butting in here, but my sense of humor got he best of me.
I think it is very nice of you to save all those books for Ned.
Since I like figures, here is my suggestion:
First you must create a super spreadsheet on your computer. Label it 'Ned's Load'.
Then keep track of the weight (books) constantly, as they accumulate.
Calculate the percentage of the weight of the books in relation to the weight of your RV.
Update the spreadsheet as you add books.
Calculate the fuel that you are consuming while traveling, pulling out the percentage of fuel necessary to lug those books around, using the ratio defined earlier.
You might even crank in the cost figures for fuel as you go. Certainly they will vary from State to State.
The final result will be the amount of pennies that Ned will have to cough up when he takes possession of the books to compensate for fuel used. You can get creative and really stick it to Ned by calculating overall costs, i.e. repairs, maintenance, depreciation etc. :
I guess you get the idea. Sure beats playing Solitaire on the computer. 8)
Wishing you and Ned the best from Florida, hot, thunderstorms right now, no hurricanes.
carson FL (a cool 81F)