The pet fee is a great tool, but we should be able to have a "pets or small dogs only" option.
In my case, I would like to allow pets for a fee in one of my listings, but I don't want the guest to come with a dinosaur dog just because they are paying.
The bigger the dog, the more hair they will shed around the house/apartment, larger proportions mean bigger odors and debris, they can easily break furniture or scratch a wooden floor. Plus, they don't get the same special care as smaller dogs (e.g. Chihuahuas, Schnouzers, etc.).
By the way, I have a large property with two houses inside, there is no division between the two, but they are separated by 60 meters from each other. In one of the houses a client brought a Labrador, which went to the other house wanting to attack the other guests (it was a "well-behaved dog" they said before booking). A small dog would not have done that or would have threatened their lives or children.