@Andrea Cocolin should let them know that you have dogs (you may rent to someone who does not want to live with a dog, for example someone who have allergy).It will also not look right if you have pets but ask tenants not to have pets - can be but would not be right in my opinion. 

I take great care of my buildings and market them as per allergy free, and attract tenants that don’t like pets (smell, noise, etc. ).

Also, most prospective tenants are going to find real hardwood floors to be more desirable (for the look, and if they suffer from allergies). 

Does he have any allergies?

I would personally guess that it is allergies.

The problem with carpet is that there are finicky tenants/buyers out there, who will not rent or buy a property if it has carpet (due to allergies). 

It's just a little bit, but it was yet another thing that was probably triggering my allergies in this place (Yes, I'm allergic to everything - anything with fur, most grasses, most trees, all molds....)I've painted the ceilings in the kitchen, hallway and upstairs bathroom.  

Tenants with respiratory ailments, allergies, or any other physical or mental condition relating to smoke are put on notice that Landlord does not assume any higher duty of care to enforce this section.

They could go after you for damages--having to move because of the roach infested home, all of their moving costs, they having to fumigate their stuff, because otherwise they likely took some with them, their rashes and allergies, and so on. 

I have horrible cat allergies and can no longer self manage/clean/prepare the unit when there are cats indoors.