Best Ice Machines in Baltimore MD

Called for an estimate on a specific gas test. They wanted nearly $2000 for a 2 hour test. Called 4 other plumbing companies and they all averaged $600. These guys pricing is off the charts. Do they subcontract all their work and then the subcontracts subcontract one more level down? 3 times more expensive then other companies, 4 times more expensive then an independent plumber.