Well balancing out material and costs labour costs is one thing but 2 story is quite a bit cheaper to build ; far less foundation and roofing area. It also simplifies the plumbing and of course is far more energy effective as downstairs heating will also contribute to upstairs heating. PROs can develop on this. And as Curt points out, modular is a very fast and cost effective solution which can allow you to put your pennies into better quality. Be very careful to select a known and competent professional if you go this way though, i don't know about NZ but europe abounds with cowboys ; low costers are to be strictly avoided.

So if I want to include sustainable things in my house, where should I start?

You are so right white is never out of fashion. I would set your budget and then look at your options. If you plan to stay in the house for many years then spend to the top of your budget (if that is going to give you a life time of pleasure), if you plan on being at the home for only a short time / few years then I would go mid range so it looks lovely, will have good resale value but you can invest your well earned money to go towards something else as well. Obviously Marble / Granite is the top of the range but there are so many cheaper and very attractive options these days that look just as good.

Hi all!! My parents and I are in a dilemma for what materials should we use for the cupboards in Kitchen. We're being advised for Waterproof Plywood, PVC Boards and some other options. We've already placed a concrete shelf. Can you please help me decide what material is codt effective and durable. It's a small house and we've a very limited budget. Location - Punjab, India.