I am also a teen horse lover and a new horse owner as well.
I work as a working student a minimum of 6 hours a week (usually more like 18 though) so I get free lessons twice a week (one private and one group). I also have a feeding jobs on the weekend. I feed two different barns 7 horses in one barn and 15 in the other. This feed job pays me enough to pay for both my horse's board and farrier costs.
Also this summer I will be working at the horseback riding camp the farm offers which will go straight towards the board fee.
Check around for summer camps looking for camp councelors.
Best of luck getting your clydesdale. When I was a kid in pony club I had a friend who had a clydesdale. We all used to beg her to let us ride him. I can understand why you want one, they are gentle giants.
My mom's dream horse is a friesian. They are beautiful, but I've always been a bit more partial to TB and arabians, although arabs have a bad rap in the hunter world. I think I read the Black Stallion too many times as a kid, lol.
If you are that close to ranch I would definately look into that. Not sure about your area, but if you have a lot shows that go on, you could be a groomer. I used to go with my trainer as teen and she would pay me to groom all her horses and braid their manes and tails. It was mostly on the weekends and it helped pay for my own lessons and shows. If you don't have to clip them, there really isn't much stuff you would have to buy either.
Like literally, I could almost throw a rock from my house and hit their barns (notice I said barns, they have about 6). I'll talk to them, their grandson and his wife are great friends of mine. Actually, I'm pretty close to the whole family.