I wrote a paper on how to control the project cost escalation that is relevant to this discussion. Typically 90% of construction projects are completed over budget with median being 28% over. <a href="http:&#x2F;&#x2F;leanconstructionblog.com&#x2F;Target-Value-Design-as-a-Method-for-Controlling-Project-Cost-Overrun.html" rel="nofollow">http:&#x2F;&#x2F;leanconstructionblog.com&#x2F;Target-Value-Design-as-a-Met...</a>