I've met several singles and couples who travel in small diesel C / B+ units over the past year.
A small DP class A is going to be over 30'. On a rainy cold day, you are going to have to go to the store in your rig because the motorcycle is unsafe. Parking and such are going to be a real pain.
Folks with 24' Mercedes sprinter chassis units (some are called Class C, some are called B+) have almost no trouble going around in their rig when it's not motorcycle weather. (Heck my Ram 2500 is 22 feet long - so where I can park the truck, they can park their Class C.)
I would suggest you look at those units - Winnebago, Thor, and other manufactures make good units which get fuel mileage the rest of us envy. (Well, Winnebago/Itasca do make a Class A on the sprinter chassis).
Your biggest issue is going to be reliable internet. Because the great locations for solitude are often completely outside cell phone coverage. I find an ATT smartphone with tethering capability and a Verizon MiFi give me 40GB of data per month capability - and one works well whenever I have cell service. But I still am without cell/ internet about 1/2 of the time in really great locations away from cities.
(If 20-40GB per month is not going to work for your business - you might need to reconsider the whole RV thing.)