Jennifer, I am a licensed HVAC technician in MA and an engineer for over 30 years. In stumbling upon your post I joined to urge you to please stop and reconsider what you are doing Monday. There are many ways to provide A/C for a house and the best way to start is to do a heat load for your house. If that has not been done you are being ripped off. The question of vents and dust and moulding can easily be answered with a unit from http://www.unicosystem.com/ These people and a couple of similar companies units are made for this condition and will answer all your questions. Delay the work and call the company directly. Simply put they made for historic restoration jobs, the move less air so smaller vents or different types usually hidden, less air means less dust blown around. Yes they are just as quiet or more when installed correctly and you will be happier! Cost is comparable and if you have not been given this option you need to question if the contractor is the right one for you, he should have offered this to address your particular concerns.

Update: Builder did not arrange a meeting with the HVAC super. However they did pass on our concerns, and some changes were made today. Two smaller vents were installed in the living room several feet away on either side of the light fixture instead of the one large central one. So we are happy with that. The family room is now also two smaller vents, but they are much closer still to the center of the room and will right right above where each couch will be in that room. This room is 18 x 22, with a sliding glass door behind where the person taking the picture is standing. There is also a 12 ft. wide opening to the kitchen/ breakfast nook behind and to the right of the photographer. The unit is a Lennox 14HPX-048-230-18. Will be engineered with air handler to be a 15 SEER. I asked about the air handler model and I am still waiting to hear back. I know this system gets bad reviews but we just don't have the budget to do anything else right now, and builder, not being custom, won't let us shop around. I am still concerned about this family room. Should I request another change, moving each of the two air diffusers even further back towards each perimeter? Should there be a third one anywhere, or is the two enough?

I'm partly done - it will probably be a year-long thing, LOL! And I probably won't do the kitchen at all, since I just repainted the ceiling white - I'll wait til it needs painting again before I tackle that again -- otherwise, I think my dh may indeed kill me. The parts of the ceiling that I have done the wall color look very nice though. And it's so much easier not to have to edge at the top of the walls, LOL!

My experience in selling our house in Oct 2009 was atypical for our area ( nothing was selling in out area or neighborhood, but I think will relate to your situation. The house was built in 1990. I have not read all of the responses but here goes. We painted the entire house to a neutral walls and white trim because it needed it. We did not paint the brick FP. We removed the wall paper in the FR but left the wainscot and folk wallpaper in the Kitchen and Bfst nook. Realtor had a cow and said house would never sell, but this still looked great. Maybe not HGTV but I was tried of taking wallpaper down... We replaced all of the carpet- bedrooms, finished lower level and FR- with a neutral flat more commercial berber from HD. Because it needed it and looked worn. This was cheap with free install. We had already moved out of the house and the upstairs had no furniture but all the windows all had white wide slat wood blinds. The living room had my Persian area rug and the piano. The dining room had a garage sale round dining table with a floor length canvas drop cloth for the table cloth and four black dining chairs. Oh and an ivy plant in the center. The family room had my old sofa with a white slipcover and my old leather ottoman with a copper tray on it. Oh yeah and two throw pillows. I changed out the kitchen knobs. I spray painted the light fixtures bronze, these were cheap shiny brass. Our house was spotless. Inside and outside and empty except for the mentioned items. The realtor listed it on a Friday night and it was sold by 7pm Sat night to the first people who looked at it Sat am. For asking price. Within 5% of two comps. We became friends with the buyers as we built a house on our adjoining property and they said they chose our house because it was newly painted and had new carpet so they didn't have to do that. They loved the wallpaper in the kitchen but immediately changed out the kitchen knobs. They wanted to buy my "dining set"... This house was under $500.000 and we spent under $3,000 to do the carpet and I did the painting. I will say that if the house was a more expensive and more upscale neighborhood, I would still have emptied and minimally staged. Nobody is buying your décor and even if you have to pack up and put everything into storage and live like Spartans I would do that at least. When we started cleaning it became apparent that the paint and carpet needed to be done. Once a house is emptied unless its newly painted even if clean it still can look grungy IMO. Sometimes people give a painting cash allowance at closing - that might suffice for some buyers. Most of the staging/updating I believe if for a certain price point. You know to help buyers choose between several closely comparable properties. If your home is appealing to a certain demographic because of a higher price then wouldn't those buyers want to pick their own flooring, paint colors fixtures etc?