I never go buy price, I go by quality of work. I won't use a shop if I haven't seen their work on some ones car.
The difference between $150 and $250 don't mean nothing if they f up the job. I only plan to pay for tint once so I go with reputation of work.
I would call local dealers that you like and find out who if anyone they use or send their clients too, then look at the level of work and their shop.