Charging Extra for Individual Turnout

The barn i board at didn’t have an individual turnout for my horse ( young, exuberant ). I ended up making a small pasture using a tiny corner of a 5 acre field. My money, my labor. Was working ok but now my issue is other people use it & my solar fence charger is broken & lots of poop. (I have cleaned it twice so far). Hopefully things will improve when weather does.