The Australian Greens are preparing to unveil the most ambitious plan yet to get young people into homes, costed at an extraordinary $51 billion.

The $51 billion figure is a net saving to the budget rather than a cost, calculated over 10 by the Parliamentary Budget Office.

Greens leader Richard Di Natale wants Australia to take more Rohingya refugees. Credit:AAP

The three-point plan, Houses for Young People: Freeing up Investment Properties, would phase out the capital gains tax discount available to property investors over five years.

During the first year, the standard 50 per cent discount on capital gains tax would shrink to 40 per cent, to 10 per cent after four years and zero after five years.