How best to manage access control in an apartment block?

[Leanne Hunt]

I am having some trouble keeping tenants in my 8-unit apartment block. Some tenants have broken leases on account of getting into debt but it seems security may be an issue. The block is set close to the street with a wrought-iron gate leading up a short path to a set of glass doors. Neither the gate nor the doors have locks. I have looked into several methods to improve security and would appreciate some thoughts from the community. Should I go for remote to open the gate and keys for the glass door? Should I go the whole hog and emply a security guard? Or should I opt for the digi-pad where tenants enter a pin at the gate, and where each flat has its own telephone intercom with a button to admit visitors? I'm worried about incurring lots of repair costs if the equipment gets broken.