I personally like the style of mouldings to stay consistent or at least not clash. When a previous owner renovated our 1914 house they used the thin (2" maybe) golden oak type trim in the kitchen and dining room, which was completely inconsistent with the original fat, 6" dark-stained trim everywhere else. So there were 2 problems, they weren't the same style and they weren't the same colour. Drove me bonkers and I'm very happy to now have trim that matches the original. Mind you it's white, whereas the rest of the first floor is dark, but the style is the same and that's what I was most concerned about. It actually turned out much better than I expected (having different colours) but I tied the dark trim into the kitchen with wood chairs and bamboo blinds to match etc. That being said, if you ever do intend to match the rest of the trim to the kitchen's, I'd go ahead and do it while your reno'ing.

All valuables hidden and locked up if possible. All precious breakables packed securely and moved to the opposite end of the house; as far away from the mess as possible. All everyday items in plastic bins within easy access. During drywall repair, and priming (fumes), a sheet covers the hallway opening to prevent some of the 'flow thru' although not entirely. Our one water supply is in the back of the house and the work is in the front so frequent trips to the water closet tracks dirt, dust and crud thru the whole house. Daily vaccuuming is a must for sanity. Be aware that drywall dust will find any available opening to float thru. If possible, opening windows helps. With the heat this summer, it's been few and far between that we were able to have them open. The few times we did, the screens were coated in drywall powder that turned to mud upon blasting them with the garden hose. I'm pretty sure 'construction muck' has become a food group for us! Ha Ha! Sometimes, the only sanity-saver is going out - to eat, to window shop, to wander aimlessly thru the grocery store all the while thinking about how much money I'm saving not buying half the ingredients since we're oven-less and burner-less anyway! We also use plastic to cover the big items that could not be moved to the other end of the area. The heavier plastic & tarps are re-used daily and the thinner plastic gets pitched once torn.

schoolhouse - If your furnace is oil, you may have a serious problem. The boom means the fuel is igniting late after it builds up. This happened to us and the "boom" blew the exhaust duct clean off the furnace and hot gasses started filling the house. Luckily I was home and went down to the basement to investigate and shut it off. The fix was to simply adjust the ignition points on the burner. Yeah, those galvanized pipes do like to rust. Mine are approaching 100 years and the ones I've peeked inside of to the water heater are almost completely clogged with rust. I just replaced my kitchen sink drain pipe after it quit draining permanently and found the metal in the pipe was so thin at one place I could poke my finger through it. It crumbled like aluminum foil. In all my remodeling, in the old construction, I've had cracks open up in walls, toilets that start leaking, wiring that mysteriously stops working, cold drafts that suddenly appear, but the new construction so far seems immune to the disruption. Score one for modern building techniques!

Johnson Brothers is right, a good architect or Kitchen Designer can work with many styles. I'm talking about architects for the overall flow and design of the home and a Kitchen Designer for the kitchen design...not an interior designer or similar. Interior designers will also help with colors, materials, etc., but from what I've seen, neither architects nor interior designers are very good at kitchen design (at least not good functional design).