You may offer different packages or add-ons that require completely different terms and conditions than your normal offerings. You can add custom fields into your terms that will apply only when a specific package is booked.
Go to Manage -> Business Settings and click on the Terms tab.
From your Terms page, click on the Create Optional Section button on the right.
Give the new terms a title and a token.
Write or paste in the terms that you want associated with the token you entered above.
Select which packages these terms apply to.
Click Save Changes to create your new terms section.
The new token you just created will appear in the right sidebar.
Now just copy and paste the token into your main terms where you want the package specific terms to show up.
When a client books a package that you have created specific terms for, they will see those terms in their contract.
Learn about dynamic terms at 5:55 in this video