You can turn the vent for the vent hood and route it to an outside wall. (There are some rules for it, I believe it is recommended that it have no more than two 90 degree turns, to work efficiently.) The reason I mentioned you may want to plan for it now, is that if you need a larger duct (say 10"), you may want to account for that so it will fit in your ceiling joists, and you can avoid having a soffit. If you know which range or rangetop you will choose, then you will have a better idea what type of ventilation you will need and what size duct.

"Is it necessary, or a good idea to replace the areas of the house that were not included in the remodel, since the house is 25 years old since it is M copper?" Yes, do a total replacement, as the copper has reached it expected life expectancy. CPVC is widely used in mobil homes due to it's flexibility and lack of out-gassing at the glue joints. "Also, the plumber wants to use several island vents, including one in a bathroom. He doesn't want to go through the roof." You need to have a short and serious chat with your contractor about quality of workmanship, because this is BS. "And yes I think this is all about the general contractor saving money, my husband is afraid that if we push him too hard about the pipes he will charge us more on change orders/items that he has completed, but will not give us a price on." In many states all change orders are required in the business and professional code, to be fully priced upon presentation for signature. But, why would you sign an authorization to proceed, without knowing what it cost? "We ask him how much adding or changing something will be, instead of telling us he just builds it without giving a price or change order. We have asked him several times to write it up, but he does not, Its really irritating and yes my contract states that he must give us the change order in witting, before he changes anything." If you know an attny. better yet where he lives, don't wait until monday, race over to his house and break in.

"Baloney, I don't believe it. What is the source of the information for these claims?" A common example is that water heaters last an average of 1.5 to 2.5 years around here. We're on a water system that runs from 25 gpg to 35 gpg hardness. Replaced my WH in 1995 and still on the same one so that's 7 water heaters I haven't paid for at an average cost of $800 installed or around $5600. My softener cost me around $700 so I'm $4900 ahead... even considering that softener salt cost me about $60 a year... good enough cost offset for you? I haven't has to touch a faucet to fix a drip or open the toilet tank once since 1995. Appliance repair people I know tell me that hard water kills tankless water heaters and front load washers and dishwashers. Oh yea, our dishwasher was installed in 1995 also and it hasn't skipped a beat and the ice maker in my 1995 fridge works great while my neighbors who don't have a softener don't have ice cubes but they do buy bottles and bottles and bottles and bottles of bottled water. People tell me, and my wife agrees, that clothes last significantly longer when washed in soft water. I can tell you that clothes washed in soft water are markedly more comfortable to wear... far less stiff and scratchy. "Some also think it should be plumbed to hot only because the elevated salt level isn't healthy to drink, but opinions are divided on this..." They may think but they don't know what they don't know. No ion exchange softener that is operating properly adds ANY salt to the softened water. Got it, that's ANY salt added. What is added are sodium or potassium ions not salt. So, for you who think, how much sodium (not salt) is really added to soften water? The formula for added sodium is 7.85 mg/l (about a quart) of softened water per grain per gallon of compensated hardness. EXAMPLE 20 gpg * 7.85 = 157 mg of sodium added per liter of softened water, not salt. How does this sodium content of softened water compare to sodium found in common foods? The table demonstrates the usual range of sodium in common foods. Food Amount Mg of Sodium Ketchup 1 tablespoon 204 Milk 2 Cups 226 Frozen Peas 1/2 Cup 295 Bread 2 Slices 322 Corn Flakes 1 oz. 260 Parmesan Cheese 1 oz. 528 Tomato Juice 4 oz. 504 Tomato Soup 1 Cup 932 Chili 1 Cup 1194 Beef Broth 1 Cup 1152 Get a softener and stop eating tomato soup. Softening only the hot water will give you hard water at every appliance and fixture where hot and cold are mixed. You'll pay for soft water and not get it. Any water treatment pro who advocates softening only hot water is either stupid, a scam artist, or to install a softener correctly would be too difficult or too expensive for the homeowner and they don't want to lose a sale (see scam artist). That you don't like the feel of soft water is a valid criticism for some and data suggests that there is an acclamation curve of about 6 weeks and getting used to using far less soap and detergent.

So... If I had access to pipes (such as doing a remodel) I would just replace them. It's easy, and completely resets the clock. If you have some corrosive issue then use PEX instead of copper. The thing is that there is a lot of discussion about chemical leaching, long-term effects of chlorine, physical wear (from water moving over it) with regard to both copper and PEX. Those issues have been determined at this point for copper and PEX... I don't know about epoxy. I would also think that some of the long-term effects are really dependent on the installers: Was it mixed properly, was it cleaned properly, etc. I'm not sure how it could get NSF certification with the variables on each installation. Also, how are repairs/modifications handled? If it wasn't accessible (slab), I might be more willing to consider it... but would really try to go with what has a long history of use instead.