You dont’ mention how many horses. That will impact price, because the more horses, the greater risk for problems arising, the more responsibility, the less able I am to block off time to work elsewhere.
If you want someone brainless to throw food, clean poo, fill waters, then pay them $7 an hour and keep your fingers crossed. Any old high school kid should be just fine. Provided they actually show up.
If you want someone who’ll walk a fenceline daily, ensure the water’s off and tub isn’t leaking, check shoes/ pick feet, recognize colic, know how to treat a laceration, flip a cast horse, who can communicate succinctly with your vet and assist in an emergency situation, then the first hour is $35 and each additional hour is billed at a lesser rate depending upon layout of barn, horse manners, equipment, etc.
If someone wants me to stay on the property, prices average from $80 to $150+/ day depending upon headcount, and the items listed above. And yes, it would be nice if you asked me what I eat for breakfast and stocked the pantry with that, but I certainly don’t expect it.