When I signed up with Dish, I was advised to go talk with the local Dish dealer, sign up thru them, so they can do the installation.  If you sign up on-line, or over the phone, you can have anyone from anywhere do the installation.  IF you have a problem after installation, and there is a problem, it is difficult to get it taken care of.  If you have the local DISH retailer do the installation, and there is a problem, it is much easier to go talk with them face-to-face and get the situation rectified.