This is EXACTLY why I would be hesitant on becoming a landlord. Anyway, for me, a number of questions come to mind.. did he have a property manager and a live-in superintendent? Did he have a security deposit? Did he require one prior to them moving in? Did he do a background check? Etc. etc.. If not, then that was a big mistake right there. The property manager could have kept an eye on the place, and the live in super could have done random periodic inspections to make sure that the apartment was in working order, and that the appliances were still there.
The cops may not have been able to do anything at that moment, but there is a lot the landlord can do from a legal perspective.
For one thing, if he did his homework before becoming a landlord, he could have required a valid ssn, 2 yrs worth of paystubs, drug testing, no criminal record, credit check, and a background check on the people before allowing them to move in. This way he would have had an idea as to the kind of people his tenants were and also could go after them legally in court should something like his happen. He could have also taken date stamped pictures of each of the units before tenants moved in, an kept them on file, and does the same after they had left.
This is also why you have a deposit. So that should something like this happen, then they don't get their deposit back. I would make sure that the total cost of the items did not exceed the cost of the monthly rent, and I would require at least 2 months rent as a security deposit and they would also have to pay the first and last months rent prior to moving in.
So, if I am charging, $1200 a month in rent, they would need $4800 to move in. They would have to be LEGAL U.S. citizens of this country, and with full working comprehension of the English language. They would also have to show me their pay stubs from the previous 2 years, and they would have to be employed by the same company during this time, and with excellent employer references. They would need good references from previous landlords, excellent credit, no criminal record, and they would also have to pass a drug test.
If the rent was even 2 weeks late, then I would have made sure that the Super and property manager was there yesterday, to find out what was going on. And I would have made sure that I had direct contact with the tenant themselves.
It might seem harsh, or a bit much but sometimes you have to be this way to protect yourself. I know this because I am currently a renter in NYC. These things are required of you before you can even be CONSIDERED for a lease.
I hope that the appliances stolen weren't high end. I know this may sound classist, but I think that high end items are better reserved for high end people. I would put these items only in the super's apartment, as a thank you, since he would be living there, and would be making the repairs in the building and wealthy or financially stable tenants. Otherwise, only cheap, standard grade appliances would be put in the units, or, they would have to supply them, so that I wouldn't lose out on my investment should something like this happen.