Also the ladies in your group will let you know what they are comfortable with and what not. Also remember "worth" varies according to person (remember birchbox threads lol). I could have a Dior foundation that is 3 shades too dark or light for me so to me it is "worth" very little but for you, you may be willing to throw in several items to get that one thing.
Most ladies are super generous and will want you to have things that make you happy and part of the fun is the chit chat and anticipation! Plus when something you put in someone else is excited about it and takes it, it is a wonderful feeling! (right up there with reveals in big exhanges!)
Gah (insert swoon emoji here!)