If you're boarding your pet at a pet sitter's home, please ask the pet sitter what his or her requirements are in terms of vaccinations. Your pet obviously needs to have all vaccinations that are legally required, and you should hand the vaccination booklet over to the pet sitter for the duration of the booking. The pet sitter will also let you know whether they require your pet to have a preventive tick or flea treatment applied.
If the sitter has pets of their own who will come into contact with your pet, make sure to ask the pet sitter which vaccinations their pets do or don't have.