I recommend having the TV in a separate well-insulated room if you're having a great room/open floor plan. We combined a play room/media room and put french doors on so TV is visible from great room/kitchen, but noise is contained. Also, love having hand-scraped distressed wood floors that have withstood our kids and dog. Quartz counters have been proven crayon/paint/marker/anything-resistant. A mudroom with cabinets helps contain backpacks and coats by entry (ours is by garage entry since that's how we get in the house). Maximize built- in storage in every room--it's nice to have the option to store away all the toys/school projects/art supplies where they're used and played with. Consequently, we also put in a walk in pantry to store packaged foods and craft supplies. Can keep going, but these are good to start with. Goodluck!

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.

We asked a similar question when we bought our piece of bare land. We were advised that building a simple shape would reduce costs... so we've built a t shape. Single story is almost always cheaper. We have a builder who is happy to let us do a lot of work with him. We also choose to live on site, which saves us a lot in fuel. The kids and I clean up the building site most days. We've been able to separate the rubbish out between actual rubbish and recyclable material. As for cladding, we were going to do a mix of corrugated iron with plywood board and batten. But given some of the additional hassles, I don't think there's much in it cost wise. However, in saying all that, we chose to invest in long term benefits, so our house is exactly what we want and should be cheap to run. We were hoping to build for $1800 /sq m but we're still coming out at about the $2000 mark.

In my opinion I perfer option 2 from the perspective of enjoying the sun in the evening and having the option of entertaining more so in the evening given the sun and house orientation. See you have a couple bi-fold doors in the living room so assume this leads out to a deck or some outdoor area for entertaining. Also the 3 main bedrooms will get the morning sun so will warm up till midday/early afternoon. Some something to note that Bedroom 4 in both options would likely be the coldest room in the house so probably some heating options would be required for this room. Some initial thoughts based on your plans - hope that helps