I would like to pre-authorize the full amount of the upgrade when someone buys a trial. For example, the person pays $1 for the trial and the upgrade is $30. I would like to pre-authorize, or block, $30 on the customer's card. Is this possible? Follow No. Please use the comments section below to ask any additional information. You can also contact us at email@example.com Related articles Does Vendo support PayGarden?