The climate in Australia is considerably warmer than it is here. Just think for a moment about the winter we've just been through, and the winter last year - and you still think you want to keep a dog outside? I am beyond words.
Thankfully, no reputable rescue will rehome to a family that wishes to do this - if I was doing the homecheck and got even a sniff of this as an idea I would immediately start alarm bells ringing. Not being Australian, I've no idea how they generally treat their animals but I can say that being British, the whole point of a dog as a companion animal (as opposed to a working dog) is just that - a companion, usually kept in the house, so you can interact with it, and it has the benefit of warmth, shelter and protection.
Even working dogs such as police dogs, gundogs etc that are not kept in homes have the benefit of properly constructed kennels that ensure the dog's safety and wellbeing, including warmth in the winter and cool in the summer, along with protection from wind, rain and so on. This is not the same as some ramshackle "doghouse". 
One of the things I say repeatedly on threads about dog ownership is that all the adults in a house must be signed up to the commitment, financially, timewise and so on - you are looking at another fifteen years. Reading your post, you don't sound very keen, and to be frank, neither does your husband - I genuinely hope that you both decide that having a dog is not for you.
Another thing, in Australia, I understand gardens are much bigger - your DH's proposal will be deeply unfair on your neighbours, and as others have pointed out, will lead to the Council being called along with possibly the local Dog Warden, RSPCA and so on. Do you really want a bevy of officials descending on you? Remember that neighbour disputes (such as over noise) HAVE to be disclosed if you decide to move - this issue could make selling your house more difficult, and sour yr relations with neighbours.