Hello,
You can not force them to move unless they have broken the lease. If you intend to put the house on the market then you are permitted to do so. If you are untruthful in doing so they could come back on you for a illegal eviction.
The good news is since you are allowing them to continue with the lease once the lease has expired you can do what is called a tenancy at will. Basically this is a agreement that can be continued indefinitely or can end once either party gives a thirty day notice to vacate. You would not be required to put the home on the market either.
Here is a link with further information on the law as well as eviction requirements and Tenancy at will. Attorney General's Guide to Landlord-Tenant Rights,
Walter
Legal C&onsultant
Specializing in all aspects of law including Family, Real Estate, Employment and Consumer Protection