Assuming you are registered for BAS and have sufficient turnover to be making claims, my understanding is that yes, you will need an accountant for your end of year return. And unless you are a registered tax agent, I suggest a bookkeeper as well.

Your sole trader setup may have slightly different requirements, but here's how we manage the accounts for our P/L company structure:

1. Using Xero (cloud-based package) we enter transactions and reconcile accounts each month, in-house. It's easy for us because we don't need payroll functionality, altho' different businesses may require different levels of expertise
2. On a quarterly basis, bookkeeper checks entries, generally cleans up any mess that may have occurred, prepares and lodges BAS return. Very cost-effective, only requires a few hours each time
3. Bookkeeper submits accounts to accountant annually for tax return preparation and lodgement. Accountant bills for services rendered, which are the bottom end of the scale due to the preparatory work having already been done. Of course, additional fees will be charged for advisory consultation and the like.

Overall, it's a streamlined and efficient process. It does require some input from us, but it's not onerous. I suspect many small businesses conduct their accounts in a similar fashion.

Of course, I'm not an accountant so someone far better qualified may provide a different answer.

Understand from your query that you are a small business owner having a sole trader business model.If you have prior experience maintaining your books of accounts as well as dealing with ATO you may not need book keeper to start with In case if your business grows and do not find time and energy to do the book keeping as well as meeting GST compliance , you may need the assitance of the book keeper as well as Tax Accountant or Tax Agent . Many of the Tax Agents provide the services of Book keeping, Accounting & Tax Compliance services and the cost varies depending on the nature and number of transactions, For complex tax advisory matters the cost is fixed depending on the time spent by the Tax Agent or Advisor.You may please feel free to contact me at Taxfin Business services if you need further clarification or informartion in this regard. My name is Sathyanarayanan Srinivas and my contact number is 0424419130.Please visit www.taxfinservices.com.au for detailes on services provided.

If you are a sole trader, you do not have to have a book keeper or an accountant. You can keep track of your income and expenses in a spreadsheet and file your own personal tax return at the end of the financial year. No need to file a business tax return.

If however you do a lot of small transactions (debit and credit) in your business, you might want to consider using a book keeper to help you keep track and save you time.

If you also want to have a financial statements at the end of financial year (balance sheet, profit and loss and cash flow statement) then you need to get an accountant.