Multifamily Common Area Electricity

[Chan K.]

Dear BP Landlords,

I own some multifamily RE. I have some trouble lately, where my tenants don't turn off the light in the common area in the hallway or basemen after they stop using it. 

Do you ever run into this problem? If so, can you share your solution with me? I am envisioning some switch or light control that would time out if it is on more than certain xx minutes. Do you know of any product?

Thank you ahead.

-Chan-