Maynard Hill, did it on a shoestring, in 2003 with a 6ft span model plane
Strict rules set by the Switzerland-based Fedration Aronautique Internationale demand that a model weigh no more than 11 pounds. So Hill and his 12-man team spent five years developing a miniature satellite-guided autopilot capable of navigating the Atlantic. Even more daunting was how to fly 1,888 miles on less than a gallon of fuel, which was all Spirit's tank could hold and still make weight.
But I can't imagine any project with a budget less than a million or two registers with HMG.