If you did not advertise the property as available for rent (i.e.; for sale or rent) then the property should be taken out of service and converted to personal use one day after the last renter moved out. Any expenses incurred after that date (i.e.; maintenance expenses) incurred after that date are not deductible on the SCH E.
Typically what I see with a "for sale or rent" situation, is the rent is set high enough so as not to attract potential tenants, in favor of potential buyers. That way, the requirement for the property to be "available for rent" is met.
