Thought it would be interesting to compare......
I take extra flowers, decorations, sugarpaste, edible glue, sissors, non toxic glue, ribbon, piping bag with royal icing, fat brush, small brush, little cup for water......some valium & a gin in a tin (just kidding about the last two!)
AI take extra o everything (buttercream, pearls, etc.). I also have a large & small offset spatula as well as a pointy offset spatula. I also have scissors, paint brush, tweezers. May seem odd, but I bring pruning shears in case the florist neglected to prep flowers. I also bring hand towels & a small bottle of water.
If there are gumpaste elements, I make at least one extra and bring that.
Always bring camera, extra battery, & extra memory card.