- dog treats
- a mini notebook and pencils in case he needs to jot something down or has time to sketch
- a small sewing kit
- reusable grocery bags all folded up small (never know when you might need to make a purchase or have something to carry, and no need to waste plastic)
- his favorite photo of Tony
- cigarettes and a lighter (for camaraderie purposes)
- condoms and lube (OBV)
- a couple of those portable back-up charger things so Tony’s devices can stay charged if they get stuck somewhere
- a couple image inducers / photostatic veils (as far as I can tell these are comparable to each other in the 616 and MCU universes, respectively? anyway they wouldn’t be much use to Steve while he’s in costume of course but other team members could use them in a pinch)
- back up comms for the team (Hulk and Thor are always breaking theirs)
- back-up hearing aids for Clint
- a deck of cards in case they’re stuck somewhere and get bored
- small emergency supplies, like power bars, emergency rations, water filters
- an epi-pen
- coloring book pages and little colored markers to occupy kids with when necessary
- whatever, ammo or something I guess
- also an engagement ring for when he gets up the nerve to ASK TONY TO MARRY HIM 😛