Just a side note, about the vapor barrier.
Because with it, the concrete will hold moisture longer and finishing will (may) take longer. Because of this, if you are not looking, the contractor workers may slit, slice, or knife the vapor barrier just before they pour. If me, I would be there when they pour.
Also, I don't let them broom the surface, even outside. They stop trowelling too soon when they broom, which doesn't leave a good finished surface layer. Also, I prefer to have the smooth surface, although because they want to broom, they will try to convince you it is the way to go, so it isn't slippery. I find the concrete not that slippery, easier to keep clean (broom the snow off and wash down with the hose), and it takes a good seal coat (unlike the broomed surface). Just a side comment.