The helicopter featured in the Expendables 3(and seen in several pictures from the set) was rented from the bulgarian Navy and Moreto.net learnt of the conditions to rent it.
The production company rented the Panther transport helicopter for more than 9900 lev(around $6770) for every flight hour. On top of that the production company has to pay charges to the Varna airport, cost of fuel and supplies for the helicopter and crew and takes on insurance liability for the helicopter and crew.
They filmed scenes with the helicopter until yesterday(sunday) in the port of Varna.
Today filming will continue in the studios of Nu Image Bulgaria.