Not sure contacting DirecTV will accomplish much at this point. What you do want to do is review the advice you get on this web site and follow it.
First, it is cheap to run wire during construction, so don't hesitate to run extra.
Establish a central location in your new house where all of the video feed wiring will run to/from (and probably phone wiring, audio wiring, etc.). From this central location run two RG6 coax with solid copper center conductor (SCC) to each potential TV location in your new house. For rooms that could have the potential for rearranging from time to time, run wiring to opposite walls (2 locations per room). I would also run a Cat5e or Cat6 ethernet cable to every location you run RG6 to.
From that central location, run FOUR RG6 coax, or empty conduit, to an outside location. Exactly where can be tricky in advance, but the goal is for this to be the feed from the dish into the central location. Someplace in the general area of where your electrical service comes in would be good, as that provides a good grounding location.
With that wiring in place, the DirecTV installer will only need to install the dish and receivers, and do the proper cross-connecting at the central location. Quick and easy install, and no "hack job" coax running, especially to inside walls.