You have a photo booth and a DJ service, and when someone books the 360 booth, you want the premium lighting package to be reserved too. You can' list both services in the package description, then use availability rules to link the packages together so booking one automatically blocks the other for that date.
Use availability rules to link items together
Manage → Business Settings → Availability → Availability Rules
Go to Availability Rules.
Click Add New Rule.
Select the items that should be booked together — checking multiple items links them so when one is booked, all others in the rule are also considered booked.
When one item from the rule is booked, all other items in the same rule are automatically blocked for that date.
This is also how you manage double-sided backdrops. See double-sided backdrops for details.