If you qualify for a subsidy
HealthCare.gov is the most affordable coverage available, full stop. Medicaid is expanded (AHCCCS) in Arizona.
If you don't
Full-price marketplace plans are the most expensive coverage in Arizona. For healthy people, private PPOs on Cigna, Aetna and PHCS PPO are routinely 30–50% less. Arizona has no state individual mandate.
What's not affordable
Health-sharing ministries and indemnity plans look cheap until you have a claim. Ask for the out-of-pocket maximum; if there isn't one, it isn't insurance.
Arizona's marketplace is dominated by HMO plans tied to one hospital system, so people who want to keep doctors across Phoenix and Tucson — or who travel — are the ones who end up on a PPO.