Do I need an ABN & business name to sell on behalf of others when starting out selling for friends?

[nativerosella]

I'm planning to actually go into business with a view to becoming an ebay trading assistant, however I'm not sure if in the beginning just selling for friends whether I need the abn & business name or if it is only when I am actually an official trading assistant or advertising my services to those outside of close friends. I will not be treating this as a hobby, however initially as I'm building up my selling ability I'm not expecting a large profit just enough to make ends meet.

Thanks