Amid Sydney's Sunday drizzle a week ago, small business owner Gary Nissim was considering how he would best weather the COVID-19 storm. By Monday, some of his biggest clients, including travel operators and hospitality groups, had slashed their marketing spend or pulled it all together.

Within 12 hours, his revenue was cut by 11 per cent. Within 36 hours, online ad agency Indago Digital had lost 14 per cent of sales and another three clients had asked for extended payment terms.