I am in a town in SW UK. Not an expensive town.
prices here are £15 an hour for a solo walk.
The excellent ones turn up on time, and do a full walk, check they are clean and have water before leaving. (I use a dog walker when I am not at home)
They all send me a message ot say dog walked, with photo of the walk, or the map from the app.
My dog is big and reactive, he barks loads at other dogs and because he is big when he pulls to bark he is a handful. The 3 good walkers we have had are all confident to handle him, and I trust them that if he is reacting to other dogs everyone is safe.
The bad one was actually fine with the dog. She was confident with him, and I knew that he would be OK with her, but she was unreliable with timings, I wasn't convinced that he was getting a full walk, and then she cancelled for spurious reasons, which really left me high and dry as I wasn't at home, and the dog needs walking.
We only use a walker occsionally, not regularly, and we have found that the good walkers get booked up with regular clients, so don't have space for an occasional walk.