Too many variables. There is a book out that gives this kind of estimate I have seen used but I do not have one. Don't remember the name.
Anyway - Is surface flat or not, are walls straight or not, how many corners? Long runs or short? What lengths are crown pieces? 8', 10', 12'
16', etc? scaffolding or ladder? 8' ceilings? 9', 12'? Size of crew? One man, two? three? four? What's your overhead like? How big is the crown? One piece or multiple built up? Furniture to move?I would figure the price, after looking at the job, by estimating how long it would take me per 25' section doing the math then double it to cover unforeseen. If you are bidding the job against some well established folks you may have to get aggressive on price if this is your first such job. Be careful not to loose your shirt.
OK - So to answer your question. Depending or variables above, between $3 per foot for the simplest of jobs and as much as $10 or more for harder jobs. ballpark, your mileage may vary, take my free advice for what it cost you, more or less could be fair.