For pens, pencils, pencil sharpeners, paper, "post it notes", notebooks, clipboards, etc., check your local "Dollar Store". Supplies can be had cheaply there. Be creative in your thinking and buying. You'd be surprized what you might find there.
Check your local "Dollar Store" or Walmart. For example, it's good to have a flame orange vest for public service events and for emergencies when you are out and about. Walmart has them (usually during hunting season) for under a dollar.
Again, check your local "Dollar Store". Inexpensive hand tools can be purchased there and who cares if you lose or break one, they're easy and cheap to replace.