From 12 to about 15 I mowed fields and whatnot with my Dad's Farmall "B" tractor and 5' BushHog mower . Charged $7 / hr and had to split it 50/50 with Dad. Had ads on bulletin boards at local stores, and would take any job within about 10 miles. Stayed very busy with that little business. That woulda been the mid 70s.
Can you imagine seeing a 12 year old driving a tractor down the road these days?