Taking you literally. $1,000 pm is $12,000 pa. Let's assume passive income from an index fund of 12% pa (for simple maths, though it's also the long-term return of the Australian stockmarket; bumpy short-term). So you would need $100,000 invested.

To save that $100,000 in a year, working 6 hrs per weekday and 8 hrs per weekend day (impossible to keep up) is 6x5+8x2=46 hours pw = 2,392 pa. You'd need to take home $41.8 ph (after tax).

It's theoretically doable.