@ZachV wrote:
....I can claim each of these under De Minimis Safe Harbor, but do I also claim the tax on the items?
Yes, you can deduct the cost of an item (including tax) provided the item costs $2,500 or less.
@ZachV wrote:
...do I combine all of the prices and just list one number, or list them separately?
The safe harbor is a maximum of $2,500 per invoice. If you purchased the items separately, then list them separately.
@ZachV wrote:
...claiming these items will not in any way affect the supplies that I am claiming on my schedule c like the base cost calendars and shipping labels.
No, the cost of supplies you are claiming as deductions on your return will not be impacted by the safe harbor election.
See https://www.irs.gov/businesses/small-businesses-self-employed/tangible-property-final-regulations
