Yep strange way of leaving the keys for the unit in a key coded safe but the whole thing worked. Particularly as they emailed us clear set of instructions. Our unit was very clean, comfortable and stacked with all the dining utensils required for an enjoyable stay. Whilst it is a self service set up, there is a well stocked 4 Square Store and an excellent takeaways at the end of the drive. We did meet the guy who looks after the units the next day when leaving. Despite being half way through cleaning the unit after we had checked out, he invited us to use the showers and change after our sand boarding experience. Could not have been more friendly and obliging. We'll definitely be heading back.
Ps when there also recommend the sand boarding down the Opononi Sand Dunes!