Construction is definitely not considered a build noted for it's amazing cash jobs / xp jobs... The best jobs @ level 45 for construction are:
<SNIP>
If this is your first time playing, don't do a builder... and don't make a worker class character. You will regret it if you continue playing this game longer then a month.
I won't argue that construction of lower level town buildings gives crap for experience, nor that it is a financial sink-hole (though a town acting together properly takes care of that).
However, as a level 35 builder with just a few AP splashed around, I have the following available to me with just inventory/items I have found on the job:
Constructing a ranch house
Building wind mills
Iron mining
Picking agaves
Building railroad station
Building coffins
Building a bridge
Setting up telegraph poles
Well drilling
Not bad, I don't think. 4.5 weeks after starting the world, and this being my first time ever playing the West, I'm a level 35 and spending 4-6 hours a day constructing town buildings.
I still haven't figured out Fort battles though, so I may be missing out on the benefits there...