If you qualify for a subsidy
HealthCare.gov is the most affordable coverage available, full stop. Medicaid is not expanded in Alabama.
If you don't
Full-price marketplace plans are the most expensive coverage in Alabama. For healthy people, private PPOs on Cigna, Aetna and PHCS PPO are routinely 30–50% less. Alabama 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.
Alabama didn't expand Medicaid and one Blue Cross carrier dominates the marketplace, so self-employed people above the subsidy line often see very few choices — and few PPO options.