Will you have a big equipped van or mini bus where you have standing room? Or do it in a clients home.
I tried it, Had a few clients but most want to go somewhere. Kids and all. It could be successful with the right clientel. You'd have to take gas into account--gas prices going up up up again--and prevent the wax from sloshing about. There are converters for your cig lighter that you can plug the heater into on your way to the client.
There is also some heavy lifting, even a portable massage table weighs something.
And then there is the mobile credit card. And cancellations. But if you have a good plan I'm sure it'll work for you.