I had a wonderful time staying at Margaret's place, in a nice residential area, not far from the center of Wellington , and just a couple of blocks from the bus line.
The room was cozy and clean, as was the whole apartment, but the best part of my stay was Margaret herself. She has interesting stories, and I was lucky to be staying when she was hosting a small dinner party, so I was able to meet some of her friends. She was also very helpful in contacting Airbnb for me when a host in Queenstown canceled my reservation suddenly.
If you're a solo traveller looking for a place in Wellington, you could hardly do better.