How fast can I get her out?

Sold my house on Contract for Deed (10/1/14) in North Dakota. The Deed is signed and notarized, but was not recorded. The down payment was not received at signing, and we verbally agreed that it was to be included with the first monthly payment (11/1/14). I have a check, but was informed by the buyer that due to personal issues, the check is no good. She has possession of the house. Before the date payment was to be made, she informed me that she was going to Canada for an undisclosed amount of time. She had the water shut off to the home. I spoke with the "water guy"(on 11/10/14) who informed me that when he shut the water off to the home, she was not present, nor to the best of his knowledge the pipes and water heater were not drained, which can and will cause major damage if they freeze. I have no idea if the heat is on or not. Since she has not paid ANY of her payments, including the down payment,and has apparently abandoned the home (some belongings remain as far as I know) what can I do and how fast to ensure no further damage is caused?