Tucson Water has no mandatory watering days or hours; the City's drought plan says it is in Tier 2, and outdoor restrictions are only a Tier 3 option. The City's Water Waste Ordinance still applies: runoff onto streets or neighbors, ponding, broken sprinkler heads and spray landing on pavement can bring a warning and then a minimum $250 fine. Outside the city, check with your water provider (Oro Valley Water, Marana Water, Metro Water, and others).
Mowing and routine lawn maintenance need no Arizona Registrar of Contractors license under the gardener exemption, A.R.S. §32-1121(A)(16). Weed-and-feed products contain herbicide, and pre-emergent treatments are outside the gardener herbicide exemption. For pre-emergent treatments, or any company that advertises weed control, ask for its Arizona Department of Agriculture Pest Management Division license and verify it. Installing new sprinklers or sod as part of a job of $1,000 or more should be done by an ROC-licensed contractor; ask for the ROC number and verify it at roc.az.gov.
This is general information, not legal advice.