To this day, I don't see how any rescue can "make money" on rescuing horses. Feed, vet, farrier, rehab, water, emergencies, hauling, quarantine, meds, supplements, safe enclosures, covers, etc., etc. take up every cent of the donations......as they should. Adoption fees don't come close to offsetting the cost of care. The reward is in helping the horse, the adopter, the kid who always dreamed.
I remember attending a rescue conference in Kentucky years ago that was the first get together for rescues across the country. Days End, ReRun, United Pegasus, Last Chance, TIER....and others. A group that filled a small banquet room at a hotel.