FAQ Q177: What is the custom unavailability script?

Please see the last paragraph in FAQ Q137 which explains the usage of the custom unavailability script. Custom unavailability script takes the exact same parameters as the pricing script but only returns information about possibility to make the reservation (including the error message if reservation is not possible). The price is calculated separately, using pricing manager rules. Of course all other criteria for availability are also considered (including unavailability rules of pricing manager or pricing script), availability of the resource in given time, and other restrictions defined for the resource.

Note: In order to be able to define the unavailability script use this special link. You will see a new field with the URL of the script in resource settings / time-related settings.