Knock Down Rebuild

A friend of mine recently completed a KDR in north-west Sydney. While it didn't go without a hitch, it's a great new home as he says he used one of the high end professional home builders. I am genuinely happy for him and his family.

Putting aside the rent vs. buy argument, we started to speak about the different thought process that he went through to decide to do this KDR. He already had a flat piece of land with his small and cosy home on it at the start of the exercise. I assume this asset was largely paid off already. He told me he considered the below options and came up with the following conclusions:
- Renovation: he thought his original home would need too much work to be done to it. I thought it was OK, but it seems his house footprint was too small and the internals were too old. Apparently, it would cost only a little less to renovate vs. KDR. So for him completely new was the best option. He'd also need to rent if he followed his reno option, since the renos were too large a scale for him to live in. I don't know about the timeline that it would have taken to do the extensive renovations
- Sell his original place and buy a home that fits closer to what he wanted: it's too competitive (expensive) to get what he wanted, he would have to pay stamp duty, he would have to deal with real estate agents, and there was no guarantee that he'll get what he wanted. Considering his position (already owning something), I would have thought this option was less stressful option, but it didn't seem appropriate for him
- KDR: he probably would get what he wanted (in the end), he didn't have to change home address after the project was finished (he loves the location), there was no stamp duty, but he still had to move and pay rent during the 10 month build. He looked at project homes (with a slight change to the design), using an architect with an independent project manager and separate builders, and using an architect which is closely associated with the builder. He went the final option as he liked the perceived synergy of using an architect who was slightly more 'practical'. He also liked to get his own fit for purpose home

I found my conversation with him really interesting. Out of curiosity I've done my own research and reading. I was wondering if anyone else out there has had first hand experience in this area, and if there is anything they'd like to share? Also, if you have any website links or recommended builders websites would be great too, as I'm finding this very interesting. I know it was a big life-changing project for him to undertake, so talking to my friend about this first-hand was very intriguing.