If I ever build again, I would probably try to arrange everything myself, workers, purchasing materials etc. I don't think there is any advantage of getting a builder who arranges everything, unless you are limited by time. Paying builders in stages never seems to work out well. Often people are left with 70% compete and the builder has spent all the money. If you can get a good team from Java, that is a good option. We had a guy from Kupang and he was one of the best workers we ever had.
Really? I have seen people trying to sell land for the past few years, at prices of around 15 million per are.