What are the requirements to do private contracting irrigation work?

True, as long as you don't do any electrical hook up of time clocks other than plugging one in. No pressure vacuum breakers, only atmospheric. You can qualify as a handy man/ irrigation tech. Basically, you can't pull permits. Many municipalities require a permit to be pulled if any modification are done to the originally approved plans on record. So as long as you do wet checks, and small repairs, you'll be fine. Get insurance! If the water comes on and the clients windows are open, and they get something of value wet, you may become liable.