Keep in mind you do not know who will be at your door with an offer down the road---my advice is to not turn anyone off this early in the game
There is no unnecessary work here--it is all necessary until such time the decision is made
Do you know a certain school cannot make your economic needs happen?
Does your son , who is just into his HS junior year, truly know what he wants in terms of a college?
One never knows what will happen--perhaps all of your sons favorites will disappear from the race
My advice, for whatever it may be worth to you, is to keep all the doors open as long as you can