Supplies vs Other Misc Expenses?

It seems like I'm always struggling over whether to put small expenses under "Supplies" or "Other Misc. Expenses."  TurboTax's instructions say "Supply expenses are incidental items that cost $200 or less or last less than a year" - which to me makes it sound like supplies can be virtually anything (except inventory or items over $200).  Thus are "supplies" really "all miscellaneous items under $200," and "other misc" is really "other misc over $200?"

Note: I'm a sole proprietor, and do not have a separate office space.

Some specific examples: where would each of these most appropriately go?

  • chargers/AC adapters
  • wires
  • tools (< $200)
  • cases/containers (i.e. for a laptop/phone)
  • headphones (< $50 for use only while working)
  • postage

The official IRS instructions for this line says "...the cost of books, professional instruments, equipment, etc., if you normally use them within a year." Many of these smaller items I listed are not used completely within a year...but then, neither are many of TurboTax's examples (i.e. flash drives, calculators, storage and filing boxes) - which seems to contradict the IRS's instructions. I can't seem to find where the $200 threshold mentioned in TurboTax comes from.