BoldTrail BackOffice allows you to zip up closed transactions and their related documents directly from your Dropbox account.

From the Add-ons page, select the Dropbox section, click Get started, and then Connect button.

On the dropbox.com page, click Allow to let BoldTrail BackOffice access your Dropbox account.

Now you're all set! Find your transactional files in the Apps > BoldTrail BackOffice folder on Dropbox. You can also stop syncing closed transactions to your Dropbox account by disabling the related toggle on the Add-ons > Dropbox page.