In general, policies regarding additional guests for a booking on VRBO can vary by property, as each listing may have its own specific rules set by the host. Typically, when making a reservation, guests will have the opportunity to specify the total number of occupants. If a guest wants to add more individuals to their booking after the reservation has been confirmed, the best course of action is to review the property's rules regarding occupancy limits.
Sometimes, hosts may allow additional guests for an extra fee, while other times they may have strict capacity limits that cannot be exceeded. It is advisable to reach out to the host directly through the messaging feature on the VRBO platform to discuss the possibility of adding more guests. Additionally, guests should consult the booking details on their reservation page to find pertinent information about the property's policies.