I retired a few years back but still do some contract work. I was using an online service intended for sole traders which did billing, expenses and tax (it pays tax directly to the Australian Tax Office before the remainder comes to you). I found a little problem with it so spent a few weeks writing my own solution in Filemaker (I have a perpetual licence). It does everything I need and I’ve tailored it so the data input is about 200% faster than the online system. It calculates my tax base...