There is one breeder that has recently put his Eclectus "package" price up to £1200 - bird, hatch cert, tested for Psittacosis, PBFD and Avian Polyoma, 5KG food, carrier, life time support. That seems steep to me, but the breeder has a very comprehensive website that has an awful lot of info covering all aspects of keeping Eclectus parrots, based on years of experience.
We paid low end for Eclectus Frankie. Talking about him strictly as a "thing", he was shabby, rough and in need of some restoration, plus his keeper at the time appeared to want nothing to do with him anymore. Fortunately, we could see his potential and he's turned into a lovely shiny "thing" now. As a living, breathing, sentient creature, he's wonderful - full of life, character and personality, and he fits into our family perfectly.
High maintenance? Well probably, but most birds that live in your home are, and we have the time to keep our birds healthy and happy. In terms of the "ongoing cost of maintenance" for four budgies, a Jardine and an Eclectus, I dread to think, but we're managing comfortably. Jardine and Eclectus have insurance cover, the budgies do not. None of the insurers do "multi-bird" policies yet (a gap in the market, too complicated or just not profitable?), like you can get for vehicles