I will apply for an Australian temporary worker visa (457) soon and my contract is for 6 months. I also plan to do some traveling around the country before and after the contract, so I will need a visa to cover the extra days. Is it possible to request those extra days during the application?
I have a semi-answer.
Anecdodal part: I applied for a 400 Temporary Highly Skilled Work Visa for some work I will be doing for a period of about 2 months. I asked for an extra two weeks in my application for tourist activities (NB: my personal time is before the work begins, not after). According to the website for 400-class visas:
Combining a holiday with your intended work or activity may be allowed if the holiday is of short term duration and secondary to the main purpose of your visit. You must indicate in your visa application if you intend to combine your work or activity with a holiday, as the period of stay considered will generally be only for the period that allows you to undertake the work or activity.
Alternatively, you can consider applying for a Visitor visa to have your holiday in Australia. To do this, you may first apply for the Temporary Work (Short Stay Specialist) visa (subclass 400) to undertake the work or activity and then a Visitor visa (once you are in Australia) for your holiday.
In my case, since my holiday was short and since it all fell within the lower 3 month boundary, I was granted the extra time. One should note that I also requested extra time in case my work is delayed, and that my tourist holiday was for before the work (normal and potential extra) began. Basically my model was 2 weeks of holiday before 2 months and maybe + 2 weeks of work.
I was just today granted a three month duration visa which takes effect on the day that I land in Australia.
Also note that the case for you may be different because your contract is 6 months, and so your tourist time will push you further along than 6 months.
In your case, it would seem that you can apply for the visitor visa during your work time in Australia, from Australia, if it is not granted already by your visa application.
I added a letter of clarification for the ECO in terms of my dates of work, including the proposed 'extra time' for the work, and the 'extra time' for tourist activities. In my case it seems to have worked, however I am from a country which constitutes 'low risk' (i.e. I am from a country which is able to get an ETA).
As your visa (457 rather than 400) is generally granted for a longer period of time, it's possible that the ECO will take your circumstances into account if you let them know that you are seeking extra tourist time (and the dates of said tourist time). I would encourage you to explain the circumstances in a letter.
If they do not grant the visa including the proposed tourist time, I would encourage you to apply for a visitor visa whilst in Australia as per the guidelines above. Note that you cannot switch from an ETA to another type of visa while already in Australia.
I have heard anecdotally that it's possible for you to enter on an ETA and then leave Australia, flying back to activate your new working visa before you work. But I can't seem to find any sources which confirm this, and you should call the embassy to ask.