"Assuming Monis acquired the mobile using a false name, that could suggest that he had the siege in mind as far back as October, 2014," counsel assisting the inquest, Jeremy Gormly, SC, said.

Man Haron Monis.

Monis never used the phone himself during the siege, nor did he ever answer any calls made to it from negotiators, the inquest was told. Instead he had his hostages make and receive calls.

The inquest was also told that Monis withdrew $850, practically all his money, from ATMs in Campsie two days before the siege. He then used $70 of that to buy the backpack he wore throughout the hostage situation and was found with $210 on him after he was shot dead at the end of the siege.

The inquest heard he may have used the rest of the money to buy his sawn-off shotgun and ammunition.