I don't know much about the Painted Star ceilings, but if you look at page 2, mostly posts 40-48, this thread references doing a 'knock down' ceiling, which my IMPRESSION means a little less perfect of a requirement.
New build (Mason)
This theater had the NightSkyMurals guy come out and do the Star ceiling for him, is that your plan? If so, you could talk with him about the knock down ceiling vs the 'perfect' ceiling.
I am in the mid-west (Cincinnati Area), and my bids/cost to hang & finish my drywall ranged from $25/ board up to $40/ board. I think 'most' of that was the finishing part vs the hanging. You could calculate your boards x this price range and see how this compares to your $1,500 quote.
If I was covering my walls, and the 'knockdown' ceiling means less perfect, I might swing it myself. If the ceiling has to be perfect, I would definitely hire that out.... of course, assuming I could find someone!!