I am writing this post to introduce you to Iron Triangle thing.
When hiring us, your main consideration is that you cannot do the design and construction by yourself. Even if you can, it might be more difficult rather than hire a specialist and leave the problems with them.
However, on hiring, you will also have tendency to maximize the outcome and minimize the cost. You will often choose that contractors that can deliver you a product which can minimize your cost, on your desired high quality, and finished as soon as possible.