Just thinking about the other piece of this puzzle. In order to qualify as a business expense, whatever space one is using as the "business" MUST BE USED 100% exclusively for the business. I had a home office in my S&B dwelling - a converted bedroom. I could not use the bed in the room for sleeping, I could not keep clothes in the closet, or have clothes chests for example. The same is true for your RV. If you are using only a portion of the RV exclusively for business, then only that percentage of the total space can be a business expense. Although in the court case, the RV was moving about, it makes no difference if it's stationary. The rule is 100% with the exception of 14 days for other uses. In my case, the "office space" could have been used as a guest bedroom for no more than 14 days per year for example. The IRS has been pretty adamant about this going back as far as 1982 with their court rulings.
Look at it from IRS standpoint, if one could switch back and forth willy-nilly between uses, i.e. office vs. RV for travel, vs. bedroom, vs. a boat, then anyone at any time could set up some bogus business (storing inventory for example in the RV, charging $1 to friends for a fishing cruise, and similar) and claim a write-off. In order to write-off space in a dwelling as business expense, the use MUST BE 100% for the office, with the 14 day exception. It's not the time of business usage vs. the time of personal usage, it's the SPACE usage that matters. Your assertion about "primary" use as a business vs. a little time for personal use is not how the IRS sees it. If one wants a business write off for office space, then the space is to be 100% for business.
Anyway, that's the way I learned it, and as taught by my very experienced, long-time business tax accountant who's dealt with just about every business tax situation you can imagine. I'd also be cautious about the business "renting" the RV space to you for your travels. Unless this is the primary service provided by the business (renting space), then the IRS will pretty much see through what you are doing and would likely disallow this.
Good luck anyway
Linda