Is it mandatory to select the add-ons? Updated November 26, 2021 18:49 The add-ons included in the owner's listing are optional. They are offered as an additional service to make your rental experience better (for example, prepaying for the owner to empty the septic tanks for you upon return) or to provide you with an extra item you may not own (for example, paying for the owner to include a bike rack with the RV). You can choose to select the add-ons you are interested in, or you can ask the owner for more information about some of the add-ons before making a decision. Please note that some owners decide to make certain add-ons mandatory, so be sure to check their listing description or enquire by sending them a message if you are unsure.