I've started 3 from birth to 2 years old. I have 2 left who just turned 3.
Vida was 5 when I got her but hadn't been ridden much beyond green broke.
I do it myself because I'm to cheap to pay someone to do it. It does take some "just buck up and do it" attitude. I didn't think I had any but its amazing what you can do to save a $2000
ETA- I still hear complements about my first filly I raised and sold. The kids who own her can crawl all over her and ride her bareback with a rope halter anywhere they want to go. For not knowing a darn thing I guess I did ok