All too many times a bid is turned in only to be told, “We need to look at VE options.” There are plenty of mechanical units that can be downgraded, architectural features that can be sacrificed, or peel back every division to see what can possibly be optimized for that extra dollar.
Gravity often dictates storm drainage design. Pipe can only run so far with pitch before crossing over into livable space. At times, it requires a leader to drop down in the middle of the building, with the only solution being to excavate a long distance — still accounting for pitch — through the interior to reach the civils.