multifamilies door lock systerm?

[Omer Ashkenazi]

Hey BP,

I own a few small multifamilies and am now up to 14 doors.  At the moment, each unit has unique keys for the front and back doors.  So, I have about 30 keys, not including keys to side doors, basements, etc.  Right now, I am considering having a master key that will work in all doors and rekey as necessary at turn over.  This option seems expensive. Does anyone have experience with this?

Does anyone have another system they recommend for managing unit access?  I am open to suggestions!