Update:  signed for the house.  2000 Sq ft, should be done sometime between Feb and Apr.  I'll work until the end of the year to mitigate the inflation factor.
		
		
	 
Congrats on your progress.   
If you haven't built a house before, one of the biggest red flags for me that might indicate things are not going well is in how they prepare your slab.   Best practice is to have rebar on a 24 inch grid, sitting on chairs so the rebar is not touching the ground.    If they tell you that they will pick up the rebar as they are pouring it, they are lying to you.  While they might do this for photo's when the pour starts, they will abandon pretending once the real work starts and spreading it becomes more important then posing for photo's.    Rebar will end up in the dirt if they do not use chairs.  It's cheap and easy, but it trips them when working, so they don't like to deal with it if they can avoid it.  I personally space my rebar on an 18 inch grid, which they hate even more, but they deal with it.   
The other thing that happens almost all of the time is they will add extra water to the mix.  More water makes it easier to spread out.   More water is also why concrete cracks within a week of the pour.    Once all the excess water evaporates, the concrete cracks because the volume the water took has left the slab.   Good rebar will help hold it together, but if they really go crazy and max out the water, the cracks can be significant.   Slump is in how much the concrete will stand up on it's own.  For a residential slab, all you really need is enough slump for it to not spread on it's own, and pile up on top of itself.   If it flows freely, you are in trouble!!!!     Reading up on slump will help you deal with a contractor that tries to add water to the mix.  Every one of them will do this, but if you stop them, then they will do it the way it's supposed to be done. 
Since there isn't any Code outside of city limits, and very little inside city limits, the Contractor that you hire to build the house will ensure that the rebar is done right, or let it slide.  After that, it's harder to catch whatever else he cuts corners on.  Taking tons of pictures will help catch something.  I know a few local Contractors in Tyler that have been sued successfully because of the pictures that where taken during construction.