Chris&Maureen

1. Hope someone will give a best answer.
2. The time frame is different for different cases, mine took 7 days to get the first notification, then i waited for 177 days to get the second notification, and my fiancé and I are preparing the requirements to be given to the embassy, and then i still need to wait for the interview schedule for days or even weeks or perhaps a month. So, it takes more than 5 months for sure.
3. You can't choose which center you want. Mine was with the CSC. But some people also got the approval fast from VSC, so I think it's based on the cases, they study all the cases.
4. The co-sponsor can't be from your fiancé's side, they have to be from your side. If your mom can't be the co-sponsor, maybe you can start finding who will be willing to. Ask favor from friends or uncles or aunties, you'll find one. My fiancé's manager is our co-sponsor because they are best friends and he will be my fiancé's bestman so being a co-sponsor is our wedding gift from him
5. When you file the petition you will pay $340, when you got the second notification your fiancé needs to pay too, US embassy in my country asks $350. And when adjusting status we need to pay $1070, and i'm not sure for the total until the end of this journey.
6. To change or not is up to you

Hi
Not sure if you have read the guides here yet but they are helpful: http://www.visajourney.com/content/k1guide
1 - Hopefully someone else can answer this one better for you, as I have not gone through this bit personally. I have a good friend who's fiance visits frequently from the U.K. and generally never has had any problems over the years. Being honest though will count and they may be concerned about him entering with the intent to marry.
2 - 5 months is the estimate right now, you can always home for it being shorter. But best to use the time to prepare, that is also just till your application gets approved. You still have another couple months to go through the process of interviewing and such. Some info for Australia: http://www.visajourney.com/consulates/index.php?ctry=Australia&cty=Sydney
3 - No choice on which service center will work on your application. From going through it they really fluctuate one isn't really faster than the other.
4 - As far as I know, that will be all on you. It doesn't matter what he has and what his Mom can send. You have the meet the 125% of the poverty lines here: http://www.uscis.gov/files/form/i-864p.pdf, and from what it sounds like you will need to have a co-sponsor since you're not working.
5 - The fee to file is $340, and to Adjust Status it is $1070, and you will also be looking at fees at the embassy too should be covered in the Australia link above.
6 - I don't see any reason why you would have to change your name.