That's not because the buildings are in bad condition, but because many of the tenants choose to live like animals.

The streets in 75% of the subdivision are not finnished with the top coat of pavement, and I have been told that they will not until the whole subdivision is at least 80% compleete.

These are not tenants but animals.

It's "ordinary" to have some traffic patterns in carpet or light staining but it is not "ordinary" to have animal stains in 15 spots.It takes some time but you should learn quickly what is ordinary and what is not.

Or working with animal rescue, which is my personal passion aside from working.  

Not allowing pets is a legal selection criteria, unless the person is requesting a service or ESA animal under fair housing, in which case, if they and you qualify, you'd have to permit. 

We use petscreening.com for any service or ESA animals, costs the landlord nothing.Security deposit equal to 1 months rent or more. 

But it is better to abandon plastic and coated steel, since they do not differ in durability.

Yes someone who has such animal is supposed to inform you before they move the animal in ( I say animal as there are different types of pets).

As for the postcards, I listened to a BP podcast before where a person had success when the put a picture of an animal on front because the thought was people warmed to it better.