Debian home security programs?

[Karen Lewellen]

Hi everyone,
I am wondering, given how flexible Debian can be, if this idea is possible? 
If it does not already exist?
I now live  in an apartment  above a business that closes very early.  One 
thing I miss from my old dwelling
 is a sort of intercom where  people would buzz my code  which dialed my 
land line   phone allowing me to communicate with them before, at that 
time, letting them in the building.
So, I am wondering if I could combine a Linux home security program with a 
wireless intercom,  or doorbell / intercom combination that might  create 
the same effect?
I am not interested in video, just a way to  connect  with a person at my 
door if that makes sense.
thoughts?
Karen