He's left his short-haired dog tied up outdoors all night in winter, left it caged indoors all day when he's out--and today the dog choked on the leash/chain that was attached to a dog-run wire... and died.

The mindset is that if a person has more money, they can sustain more losses in their own (and so can be given a wider leash on the investment, they can see).

I do not recommend Wayfair or Amazon for furniture, if you want sturdy ones that last. 

You can place "reasonable" restrictions on them, such as requiring a Veterinarian's health report; requiring spay/neuter to prevent aggressive behavior or commercial use; animal must be in a carrier or held when in confined spaces such as elevators and stairways, and leashed in common areas (unless this interferes with the task the animal performs, such as a seeing eye dog); handler must clean up after the animal in all common areas; handler must maintain sanitary conditions for the animal including no offensive odors emanating from the residence; animal must not disturb neighbors with nuisance barking or aggressive behavior; and you can require annual updates of both the "request for accommodation" letter and the Vet report.

Consider adding some family-friendly amenities...4 square, Giant Jenga, a sturdy poolside basketball hoop etc.

I may adjust it at renewal time but not during the lease.I do not allow pets in apartments because of the high risk of noise, failure to clean up after, failure to keep the animal leashed outside, etc.I include a stiff penalty of $50 per day for pet violations.

@Justin BrownWhen you're looking at furnishings, try to get sturdy furniture that is easy to clean.

Think of it as your sturdy umbrella, always ready for that unpredictable storm.Goldilocks OpportunityThe shifting sands of the rental market in NYC offer challenges, yes, but they also provide opportunities for those willing to adapt.

Keep him on a short leash.

Especially as a newbie agent, or, what we call in the Business, a "Loose Cannon", the Broker is going to want to keep you on a short leash until you have proven your integrity, character, adherence to, and understanding of, the relevant laws.