Using steel wool to fill the gaps around pipes and other openings worked the best for keeping them out.  

During rehab we hire a company which installs Steel Ventilated metal screens on door / windows.

Now if I had another tenant ready to go and slot straight in, then sure, I would consider refunding him some rent. 

She died gurgling and gasping for air, with her cancer relentlessly choking the life out of her.The school director shed a tear at her funeral, before he manfully steeled himself and mentioned to her friends that he was sure that what had happened "was for the best."

I leave a note in the door slot that says:  "Make sure you keep paying...We know where you live.   

Solution: a nice GE stainless steel stove without the digital component, so the controls are manual at the front.

I only sent out reminders because I had a lot of law students who would have the rent check sitting on their dresser, but they were so exhausted that they'd just forget to put it in the drop slot (the owner I worked for was old school and wasn't interested in online options).It seems like the only reason you need to contact your tenants is to tell them how much they owe in utilities. 

As soon as stainless steel came into fashion I thought they were already outdated things that are going to be dated any day now. 

Or, get a real official pipe strap - the ready-made kind, or that perforated steel tape you can unroll and cut to length.

Older houses will have galvanized steel pipe which will corrode from the inside.