There is a great difference between doc (direct operating costs) of home built vs. production helios. Robinson win's hands down for production units, and as far as I know the hummingbird is the only 4 place homebuilt unit on the market today. Rotorway doesn't have a 4 place unit but they do build a slick 2 seater. Even the Robinson rebuild rates for a helo you already own to be factory rebuilt to new specs is not expensive when you compare it to anyother piston 4 seater. How bout considering a 3 seater from Schwitzer? Have you considered that, or a well maintained Bell 47 for a two place. There's a lot of product out there so take your time and choose wisely, sometimes the retail price may be high but the doc might be less then others on the market, so compare apples with apples and not oranges, or ducks! Good luck and cheers!