We ended up staying only 1 night of the 3 nights that we had planned on staying at Marie's place.
Marie herself was very responsive when we made the booking, and was very accommodative in letting us check in early.
The room itself is an annex off the garage, so seems difficult to keep clean as dust and debris from the garage end up in the space. Ours was a last-minute booking so the cleaner had not been through for a few days (as Marie told us later), so when we arrived we had to give the place a decent sweep.
The unit itself is quite small (it seems larger in the photos) and is located on the front of the section, on a C bend in a road that passes nearby. The location means that the sound from cars driving past is quite loud and continues for some time as the cars pass around the C bend. We didn't sleep much due to the noise that night, and after speaking with Marie the next morning, we booked a different place to stay for the remainder of our days in Napier.