Generic payg solar subsciption device that can work in ant system

Buy offer Details

Dear Sir/Madam,
Im looking for products with the following specifications :
I am a solar rental service but sometimes, customers dont pay up hence I need a device I can include to the solar systems already installed for the customers that can turn off the system when money is not paid and can be c=reactivated when rental fees are paid.
I am looking for a generic device ODM or OEM.