This is similar to the property manager for a rental ... the manager takes in the money for property they do not own and keeps a portion for themselves & expenses paid and the rest is sent to the owner to which they must 1099 at the end of the year.
So if the consignment shop sells the items and takes in the money and then keeps a portion and remits the rest to the owner of the items then they are also required to 1099 those folks. And with the new rules anything $600 or more must not get a 1099 issued.
Both of these businesses will report ALL the income they take in on their returns then deduct the expenses they paid out which includes the total they 1099 to others.
