It a way of setting up ads I have seen a couple of times recently - the 4900 BIN is not what he expects to get - it is only what he paid.
People are then invited to make offers.
Makes some sense if you are selling newer items.
I understand that - just strikes me it would better to set the BIN at the minimum acceptable price, then consider offers - setting the BIN at the new price is daft. Then again, I always think it would be better to split the items - particularly the cymbals. The chance of finding someone who wants that exact set up would seem low.