Interesting aside:
Having family who have worked for companies like Boeing, I know that some companies get contracts by lowballing the estimated cost and then jacking up the price later once the government has committed to whomever they gave the contract to. Most civic construction suffers from the same problem. I've heard of Northrip and Lockhead doing this, not necessarily Boeing although I'm sure they have too.
Heh, I'm working as a lawyer in Poland and I often have to deal with public order contracts arranged between government authorities and private companies - and that's the standard practice, especially in case of motorway construction...