This summer we found an amazing dog friendly place in the Kaipara. It's a privately owned headland, dog friendly with a private sandy beach!! At 1 hour 30 mins drive from Albany, Auckland it's an easily doable drive for the weekend - although once you're there you'd wish you could stay longer. We stayed for a week at the start of Jan 2015 so the weather was beautiful.
You take the main race (farm speak for the main road running through the farm) down to the beach, you really need a 4WD but you can walk it. We loaded up the 4WD daily with the dogs, chilli bins and picnic blankets and spent the day enjoying the private beach - not often you can just let your dogs on a beach and not worry about traffic, other people and dogs and them escaping (As well as steep banks it's fenced with a gate, so they are very secure). Our two dogs Kyla and Marley loved watching the cows and were very excited when we got to drive through the paddocks were they were grazing. The bach was clean and had everything you need. It doesn't have an actually oven but has a microwave, bench top elements and my fav the pizza oven - yum! The barbeque is small so if taking a family you may want to consider taking one up there. The farm is right next to the bach so be aware you do get some noise from the milking, farm dogs barking etc.... That's usually finished by 6 or 7ish of an evening. Something important to note if taking dogs is the fencing around the bach is electric and for cows (not sheep fencing that is more secure). So it is likely you'll have to keep the dogs on a long line around there. We considered the beach as the main area and they are fine off lead there.
So if you are looking for a quiet, private beach holiday that you can take dogs - I would definitely check it out.