Only sometimes, and many sets could be recycled with little difficulty. Obviously there are some regional architectural differences, but many would only be recognizable to hardcore fans, and a few cans of paint and canvasses for periodic minor modifications would not be terribly costly. Regional idiosyncracies aside, wattle and daub is pretty much the same in any locale, and its ubiquity during the Middle Ages was due to the very thing that would appeal to a movie set: It is easy, quick and CHEAP to produce. Only the Great Cities would present great demands, and much of those sets could likely be recycled as well, though contrasting Cairhiens stark lines with Caemlyns gentle curves would naturally require some rearrangement. I am not saying it would be completely trivial, but it would not be my major concern (though, if it is not obvious by now, I am fairly ignorant of film productions requirements.)


Perhaps naïvely, I figured the camera and lighting demands would not be significantly greater than for any other film production, plus or minus a few wide angle lenses. Likewise the animal wrangling, but I see your point that added extras mean added liabilities, and industrialized democracies do tend to frown on free labor (although, if it were filmed in America, the nation is moving more and more toward that "ideal" daily, but that is another rant.... )


The difficulty of securing their services for years (or decades) despite multi-year gaps in between appearances is one of the biggest reasons I think established actors would be out of the question for parts not present in all but one or two books. If memory serves, EVERY character except Rand and the Wonder Girls has been absent from at least one book; Perrins total absence from TFoH is just one more reason it is my favorite, and Mats total absence from TPoD is just one more reason it is my most despised. Aviendha, a near constant presence either with the girls or Rand between TGH and ACoS, has rarely been sighted in recent volumes, but the actress playing her would need to be available at least until the "three on a boat" scene in the last novel.

Pretty much the only way that could work would be by seeking out unknown actors, and even then their time is unlikely to remain cheap and plentiful for years unless they are rather awful actors (not exactly the ideal one seeks to portray characters of any importance.) It is another argument in favor of a series, because the most critical roles could be guaranteed work at least every year or two rather than waiting five years for two or three more books to be turned into films. Also, because TV scripts are so much less than those of feature films, characters absent for whole books could be worked into new "outrigger" sideplots of their own, and events only alluded to and/or revealed by flashback in the series could be related when they actually happened.

I am somewhat playing Devils Advocate though; I really do not expect any live action production any time soon (perhaps when the economics of crowd simulators gains the TV accessibility CGI has.) The two years of story that has spanned two decades (plus) just makes the whole idea almost completely untenable.