Grailed charges a 9% commission plus payment processing fees (3.49% + $0.49 domestic, 4.99% + $0.49 international).
Yes. Grailed collects and remits sales tax from buyers where required by law in the U.S. They also charge VAT/GST on fees in certain countries.
Grailed takes 9% of the item price and shipping combined. This excludes payment processing fees, which are charged separately.