bid for texturing ceiling

If you were gonna bid on and 8-1/2 foot ceiling project where it's just been firetaped, and they want it finished, textured and painted, and it's 1800 square foot, what would you say?

How many man hours of work would you say it is? Assume the man to be skilled, healthy, working off a scaffold, with light.

Thanks for your comment.
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Cal
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