How long after an incident can someone file a police report? And does it have to be file in the state that it occurred?

Your question raises a number of issues. As it relates to the criminal matters it may not be too late to file charges, however, the charges do have to be filed in the locale where the alleged crime(s) took place; however, your description of the event doesn't really lay out a crime. If he physically assaulted her of battered her than certainly he has committed a crime, but that will have to be done in the locale with jurisdiction back in Iowa. As to the other issues, if her name is on the utilities along with her ex-boyfriends's she should be able to contact the utilities and cancel those utilities, especially if he is not paying them either. However, the utility provider may require her to pay any past due amounts. As to rent some apartments have in their lease agreements the ability to terminate a lease upon payment of a lease termination fee. However, once again she may be required to payoff any unpaid rent. This is really about the only things she can try to do to protect her credit. The lease presents the greater difficulty because that is in fact a contract that she voluntarily signed.