Definitely get a good accountant -
eg sole trader re use of car:
- registered in business name
- keep log book for 12 weeks and work out percentage use
eg if it's 60% business, 40% personal, then you can only claim 60% of the car costs (depreciation is also divided into 40% of value first year, 30% second, 30% third year for Simplified Tax System) or monthly lease payments and 60% of petrol costs etc. You have to separate these values for every costing including car services and more.
- if your home is the official 'office' then going between 2 places of work is considered 'business', but you must talk to a good accountant about this because getting things right from the beginning will make your life a whole lot easier.
Also, setting up recurring transactions in MYOB Accounting (or whatever you use) as a system is a bonus so you only need to put the numbers in each month.
GST and PAYG tax needs to be put away in a separate bank account in order to be there when you need to pay it back to the government. This means you don't accidentally spend it and if there is any left over, it is a bonus.
There's loads more, but the main thing is that getting the PAPERWORK CORRECT first and having a good relationship with a dependable accountant that you can talk to, will make your life a lot easier as a sole trader.
Also, the ATO has good info at
www.ato.gov.au (their website is currently offline for maintenance and will return on 5 January 2009)