Animal control should also be notified of the "shelter's" activities.

What should I do?

Sounds like the usual "I bought a puppy from out of state and now it has parvo" story. Document the puppy's issues with vet reports. All...

Even though the dogs didn’t leave their yard are the dog owners still liable since their dog attacked mine through the gate?

As the attack seems to have technically occurred outside the fence, it would seem the dogs' owner is liable. The attack should have been reported...

Is a verbal rental agreement governed by law?

Contracts for the sale of land must be in writing.

The attack should have been immediately reported to both the police and animal control. Send the demand letter by certified mail/return...

This is more a consumer protection issue. Take your dog to the vet and have the injuries documented; then send a copy of the report with a...

How do pets work in apartments?

Moving to landlord/tenant, where this belongs. If the building is truly "pet-friendly" and your dog's pet fee is paid, there should be little...

The actions of another tenant are making your apartment uninhabitable - that makes this a landlord/tenant issue. Moving accordingly.

To the extent you can prove the conversion, you can sue him.

You are responsible for all harm your dog caused off your property.