Falcon757, What it costs to build a bike just as you want it depends a little on timing. I couldn't order the frameset color I wanted on a 2.8, but was able to score an end of the year type of deal on a complete bike with little added expense. That group sat in a box for awhile, but was eventually reused on my daughter's bike build. Savings on that project made a significant upgrade for her doable.
The important part of building a bike like you want it is that you don't need to get another bike for years, if ever. The bike was then rebuilt from full Ultegra to a 105 triple when I injured my knee to enable me to keep riding. That bike is now 14 years old and there is no need nor want to replace it.

I even went from STI levers to down tube shifters for the hell of it.
Brad
The CAAD's forefather: