I would agree with the other person that replied that vacation rental companies do need to have a home professionally cleaned to remove any pet hair from the home in case the next guest has any allergies to animals. It does cost extra to do this and most companies charge that to the rental guest as a pet fee. The fee should be clearly posted online and expressed again over the telephone at the time of the reservation.
I agree with you that many vacation rentals claim they are pet friendly when you are making the booking to only later have many limitations.
Before booking a pet friendly vacation rental I would ask the following questions. Do you charge and pet fee and if so for what purpose? Do you have details of a local emergency vet near the home? Do you offer a dog walking service if I am running late back to the property? If the property has a swimming pool do you have a safety fence for the dog? What are the local pet friendly parks and activities near the vacation rental?
If the company cannot answer those questions than I would say they are not very pet friendly. To really be a pet friendly accommodation a company needs to understand very dog deserves a vacation too!
I hope this helps. In Orlando many companies offer pet friendly homes for guest.