You also will need to get up and at 'em very early. A friend of mine did this, and was at the grounds at 3 am at times, to get her customer's horses done on time.
And Rubbermaid makes a very handy step stool, with handle, and storage compartment under step for your equipment, and I've seen one that had a drawer too. Great item to have.
Jessie got 20 for manes, and 25 for tails, and this was in 90's, so don't know what rate is now but should be at least that I think.