I want to get a bid for the sheetrock in a house we're owner-building, and I'm not sure what to specify. Windows & doors will be encased with trim and we want regular corners -- sharp, not rounded. We also want what I think is called knockdown finish. I'm really confused about the vapor barrier, too. We're building in Seattle and we have a choice of PVA primer or 6 mil vapor barrier. Which is better? Or do we do both? Is there anything really important I'm missing?