We were traveling with a group of friends, (two other couples - six of us in total) and chartered a private sailing tour.
We had an awesome time. The boat was comfortable, and great for the size of our group. Our captain Tim took us around Abel Tasman park and tailored our route and stops to our preferences, and he picked places we really loved. We got to watch seals play for a while and had a picnic lunch in a beautiful lagoon that we had all to ourselves, and then a stop at an empty beach.
We've all been on the water once or twice before, so we came adequately prepared with various layers since we kept hearing New Zealand tends to be rainy. Our preparedness paid off in that we got totally lucky and the day was perfect. No rain jackets needed but always better safe than sorry - the boat had plenty of space to stow our extra gear.
The wind was so perfect that afternoon, and Tim even got out the spinnaker for our trip back to Kaiteriteri, routing us a bit offshore so we could see some Little Blue Penguins (which we did!).
Sailing was a spectacular way to get to see Abel Tasman National Park, highly recommended.