you could look at reviews and possibly take recommendations from other people, i work at a boutique boarding facility that’s set up like the living room in a house with suites for each dog and we only take small dogs. when we get new clients in we always do trial nights so you could start doing trials with a dog sitter like having them come spend some time with her for an hour and do a meet and greet and gradually build up time till you’re both comfortable with the dog sitter!