Defense contractors, construction occasionally. It's pretty nuts. The east span of the bay bridge was something like 5x the original cost estimate. I think some

Defense contractors, construction occasionally. It's pretty nuts. The east span of the bay bridge was something like 5x the original cost estimate. I think some of this ends up being because of the same reasons that home general contractors end up charging far more than the estimate: modifications cost extra. "Oh you wanted this feature? It wasn't in the contract, we can do it but that'll be $X. Oh you need to include this other system? That's out of scope but for $Y we can solve it." Million here, a million there and pretty soon you're talking real money ;) https://www.wnyc.org/story/316201-brief-history-64-billion-bay-bridge/ https://www.wnyc.org/story/316201-brief-history-64-billion-b...