Cheapest new Yamaha YEP-842S euphonium.  A euphonium is a brass instrument.

tboneman --

I have found one offered at a price of just over $4600 (new).  All of
the other prices I have found for this model are in a narrow range of
$5100-5300.  If no other researcher comes up with a better price, and
this price sounds attractive to you, I would happy to post the
seller's contact information.

markj-ga

Thank you for researching that for me.  I am very interested in your
offer and would like it if you sent me the contact information for the
seller.