I'm going to have to agree with Solstice, I'd be hesitant as well. I don't want to make this sound like your a bad rider or anything, but saying that you are only 13, there are a lot of things I would have to think about if I were to hire you. You have to be in school the most part of the day and you have homework that would need to be done after wards. You would have to get a ride out to people's stables everyday because you are not legal to drive yet. People's horses and ponies might not be like the ones you're used to riding, they may not be as simple. Saying that you are only 13, right now your parents have the say in about everything. What happens if you move? What happens if you are unable to get out to the barn? What if something really unexpected happen? You are kind of screwed. You are going to have to become a very mature 13 year old to deal with the owners of these horses. People are not going to tolerate mistakes you make with their horses. Just because your exercising them doesn't mean you can't make a mistake, you have to prove to them that you are good enough to ride their horses and do it properly. People may not hire you because they think you are too young, just because you have 10 years of riding experience might not be good enough in their eyes. I hate to say it, but I don't think I let you ride my ponies. One can be a total you know what, and the other needs a strong, relaxed, experienced rider on his back, sometimes I think I'm not good enough to be riding him. It took about two years to get him to where he is today, and he still need a lot of work. You need to be ready for challenges, and you can't say to someone, "I can't ride your horse, he's too hard", people are going to think you are a REALLY good rider, and if you don't live up to that expectation...well, no more exercizing horses for other people... I don't want to get your hopes down, but you need to be prepared for things like this, maybe try retinking this a bit. Once agian, not trying to say your a bad rider. =D