17 years ago we decided to sub out our own home. Our budget was tight. We decided to focus our money on things that couldn't easily be changed later.
We spent extra on foundation, windows, roof, and high seer heat pump. We went cheap on electrical fixtures, plumbing fixtures, formica countertops, fiberglass tub/showers, etc. (10 years later we slowly upgraded those items).
Building instead of buying will get you the house that you want, and everything will be new and work like it is supposed to. Energy bills will be substantially lower for the entire time you own it. It will be worth more if you ever decide to sell. Brand new homes are cheaper to insure. New home discounts are as great as 40% the 1st year and slowly go away over a period of 5-10 yr. depending on the insurer. This is because new homes have less problems with leaks from plumbing stacks, flashing, bathtubs, etc.
Buying existing homes will get you more sq. ft for the same money. It will also get you into neighborhoods with mature landscaping and longer term homeowners where there may not be vacant land. Older homes often have more character.
Buying new homes is the highest price option. Price per sq. foot is the highest. Kind of like buying a hot new vehicle the first month it comes out. You can get it exactly the way you want it, and pick all the finishes, all for very little effort except for paying full retail. It's a choice based on your budget, and work and family situation.
We had the time, energy, and willingness to do it. You may not.
As an insurance agent I had friends who were appraisers and builders who recommended subs to me. You can get this info from your local lumber yard. Talk to the guys who do lumber take-offs for plans. Talk to the roofing supply company, the window supplier, drywall supplier, etc. The counter guys know exactly who is responsible and who is not.
By subbing out your own home you can earn a substantial savings. Notice I said EARN. Builders earn their money. We were there every morning before work, every afternoon after work, and many work days. Include most weekends too. We cleaned up every evening after each sub would leave (amazing that they don't!), and made sure materials were there for the next day.
I ended up doing all the trim work myself, my wife painted every inch of the interior, and we put down the flooring together (except kicking the carpet!). It took 7 months to complete and move in, and would have been 5 if we had hired subs for the trim, paint, and flooring!
Sometimes you can hire a builder who will sub-contract for you as a paid consultant. He will hire and manage the subs for a fee or percentage, while you pay the bills. This is a half way step between subbing out and buying new turn key, and in many areas becoming more popular. Semi retired builders often do this part time instead of having to front the money for your build. It works for both parties.
Feel free to ask any more questions. Best of luck!