find a really, really good contractor, with impeccable references, and pay him what he asks. And be ready to pay more than expected for the house.
We did this, and were very happy. We had plans from a house we liked, so that was the starting point. In our case, there were NO extras. Builder gave a fair price, and had everything included (including a couple of simple upgrades he recommended, at no charge).
That said,
What worked:
- big walk in closet
- big master bath with tub and shower
- Lots of windows, and get the good ones as suggested
- open floor plan
- big kitchen
Things I would do different:
- Heated tile Floors in all bath rooms, as suggested above.
- You can never have enough electrical outlets, particularly outside (Xmas lights, etc)
- upgraded counter tops
- Zoned cooling, more for comfort than energy savings
- if you can afford it, don't save anything for later (decks, finished basement, well not in Florida)
Good luck. The key is to pick a well referenced contractor, preferably one that has built in your neighborhood.