The first was applying for a more expensive visa than I needed to.
The second I noticed, but not chronologically, was booking a flight from Broken Hill to Sydney on Regional Express without verifying whether they take bikes and at what cost. In theory, they should but in practice, who knows. I have made an inquiry. The thing is, I could have worked things to stop riding in Mildura where I would have had more of a range of exit options.
The third I noticed but was probably the first muck-up was not checking the exchange rates. I had an idea the Australian dollar was worth a little bit less than the Canadian one. It turns out the reverse is true. Thankfully, the difference is not severe.
The fourth I noticed, but which happened before the Regional Express blunder was not to notice that the Jetstar flight I booked flies into Melbourne's secondary airport near Geelong, not the main one. This actually could be an advantage as if I found suitable accommodation in Geelong, I could start from there, rather than central Melbourne, as Geelong is apparently about 70 km to the South-West of Melbourne. The downside is that I would have to take a train into Melbourne to see the sights. Then again, after three flights, including one that comes in at number 23 of the 30 longest commercial flights list (15 hours 25 minutes spanning 3 days on the calendar so I will never see the light of day on October 16, 2011), I may simply be unable to function sufficiently to get into Melbourne!
For the latter reason, I am strongly tempted to book myself a private room in a quiet establishment in order get some quality sleep, rather than a cheap room in one of Melbourne's many quality "youth" hostels.
None of these issues are critical, and in the latter case, "it's an ill-wind that blows no good".