If you don't have a service truck, it's a no-brainer. Go out and get yourself a bunch of big Rubbermaid totes or big plastic tool boxes and equip each with tools needed for specific installs.
Store them on a rack next to the door and always have them ready to go at a moment's notice.
Yes: You'll end up buying duplicates, but you'll never forget anything back at the shop...which usually causes you to buy duplicates when you're on an install a good stretch from the shop.
One tote could be the "master tote" that goes to every job (includes all the basic tools needed for most installs: drill, bits, squeegee, razor blades, tape measure, level,
paper towels, cleaner, etc...). Make sure this one is a different color so you always remember to grab it every time.
This should put a sudden and long-lasting end to the squabbles you mention.
JB