Be sure your lease or rental agreement complies with all relevant laws including rent control ordinances, health and safety codes, occupancy rules, and antidiscrimination laws. State laws are especially key, setting security deposit limits, notice requirements for entering rental property, tenants' rights to sublet or bring in additional roommates, rules for changing or ending a tenancy, and specific disclosure requirements such as past flooding in the rental unit.
Any other legal restrictions, such as limits on the type of business a tenant may run from home, should also be spelled out in the lease or rental agreement. Important rules and regulations covering parking and use of common areas should be specifically mentioned in the lease or rental agreement.