add ons for scheduling??

How would I add in add ons to a scheduling appointment? for example i am aware of people selling gift boxes and there are workarounds to be able to add on and upsell. However, for example if i am to give my clients an option to book a massage, with a selection of various add ons that vary in price (oils, aroma diffusers, skin care etc) how would i do this? is there a way of these all being sold as a product, while still taking advantage of the scheduling system (acuity) squarespace has? the massage needs to be booked via scheduling, and the add ons can be products but can they all be grouped in the same checkout when completeing the booking?