The memorandum summarizes that reaching over a counter to take money from a cash register constitutes burglary under Arizona law. It discusses that (1) entering a store with the intent to commit theft makes the entry unlawful even if the store is otherwise open to the public, and (2) a cash register qualifies as a "structure" as defined by the burglary statute since it is used for business purposes and can be secured. Case law establishes that the crime is complete upon unlawful entry with criminal intent and that minimal intrusion, such as reaching an arm over a counter, satisfies the entry element of burglary.