@Meridith8,
I don't charge for pet (dog) on my listing and to be honest, 8 out of 10 times, it's been fine with guests usually taking their dog with them when they go out. In all 5 years of hosting, I've only been asked once if it was OK to leave the pet as they wanted to go out for dinner, and I was okay with this.
In my experience, it doesn't matter that I put in my listing that we welcome well-behaved dogs, or that they should be on lead, or only medium-sized dogs and below, 2 out of 10 will arrive with excessive barkers, let their dog off lead (one incident where dog entered paddock which is off limit and got chased by our horses or bring golden retrievers, German Shepherds and so on. In other words, some guests simply do not read descriptions of listings anyways.
As for cleaning, some dogs will shed more than others, it's to be expected. And some folks will let their dog on furniture and the bed without cleaning their paws, so that's expected too.
Most guests, thankfully, are considerate, and we continue to not charge extra for pets as this would make us not competitive price wise (there are quite a lot of Airbnbs in our area).
We think allowing for pets expands the customer base and adds to the attractiveness of our listing, so we're happy to put up with the occasional pet-related issue.
Hope that helps 🙂