The word between owner names matters. Arizona uses the legal status to determine who can transfer ownership, record loan information, transfer plates/fees and handle the vehicle when an owner dies.
OR
Either owner can sign when selling. If one dies, the surviving owner can act without a death certificate for the deceased owner’s interest.
AND
Both owners sign while living. A deceased owner’s interest must be handled through the applicable probate or non-probate process.
AND/OR
Both owners sign while living. After one owner dies, the survivor can act after providing the required death certificate.
When applying for a title with multiple owners, additional owner signatures and legal-status selections may be required even when “OR” later allows either owner to sell.