Question about changes to a sale in last financial year + GST questions

[dont_waste_dollars]

Gday all,

Im doing my first tax return and paying my first installment of gst as a sole trader and i have a few questions about that.

What if a sale made on say may 12th had a warrenty claim, that item is now out of stock and i have the buyer refunded as a result in this financial year? Do i simply remove that sale from last years books? do i keep it there and put something in this years that would be something like buyer refunded 11th JUL - $27 profit, -$20 GST etc and reference the original sale? 

Normally if i have an item refunded or its out of stock. i just refund the buyer and delete the sale from my records. ( my suppliers cover all costs when an item is returned, so i just lose the profit made)

And what if i pay my BAC for the quarter then a sale is refunded. do i minus the GST from my next one??

Basically any information reguarding sales and gst and how to manage them going from different tax returns and BAC's

Thankyou so much

[lane-ends]

By the time you are audited you are likely to have forgotton the specifics or reasons for any "adjustments", so keeping everything as simple as possible is easiest. Its part of tthe swings and roundabouts, and one of teh reasons its hard to absolutley sure of ypour profits and losses for any period until you have added all the numbers up.