If you're boarding pets in your home, you are the one who needs to make a decision about which vaccinations you require them to have - with the exception of legally required vaccinations, which they obviously need to have anyway. You can also determine whether your not your guest pets need to have a preventive tick or flea treatment applied. Make sure to let the pet parent know about your requirements well in advance.
If you have pets of your own who will come into contact with the guest pet, make sure to inform the pet parent which vaccinations your own pets do or don't have.