Unfortunately, you cannot get full child custody without going to court. This is because, under California law, child custody is something that must be ordered by a court with jurisdiction over the children involved. Thus, any custody determinations in California must inherently go through the court system.
Generally, in most US states, including California, you don't need a lawyer to start a custody case. This is because you have the right of self-representation in court. You may agree if you and your ex-partner are willing to work out your differences. You can do this by going to a mediation service.
Arizona courts consider factors such as the child's needs, parental involvement, and each parent's ability to provide a nurturing environment when determining custody arrangements. This information is often outlined in a parenting plan to ensure the child's well-being and development.