"that if the items were bought at a higher price than what they were sold at, that she could claim at them at a loss."

We went through this on another topic; these are Used. There is no Higher Price. At this point, they are not worth more than they sell for. In fact, for business purposes, you can research FMV used, from Goodwill and it's Deductible.

You don't get to use original cost for used items as COGS.

I agree that some of this is consignment. If you pay your friends everything you sold it for, that is $0 profit. If you paid your friends minus some amount for your time and effort, that is Business profit.

I'll try to find that other topic for you, but that's the gist of it.