I did both in AL. And concentrated on people who were learning to ride and learning about horses. I gave them solid advice, and lessons, both on ground and astride.
I actually preferred going to their barn/place and working with their horses, as gave me much better insight into what they were doing, i.e. high handed, letting horse run them over, and could then work with their horse too.
Amazing at how quickly they could understand why their horse was jigging under them and rooting through bit due to their high hands, when I got on the horse, and it wasn't doing it for me, because my hands were low and quiet.
It was like watching a light bulb go on!
You might charge so much for mile maybe? Not tons, but something?
I would though, set some ground rules, as if they have friends/kids/dogs hanging around, that can make it aggravating to you, and ruin lesson.
And figure out if you are going to keep to tight schedule too, as it is very easy when you go to them, to waste time talking and such.
Horses make me a better person.