Boy, this is going to cause some upsets for some, I can see both the for and against cases for this proposal.

I wonder if in the case of complexes of just 4 units, if three decide to sell the fourth owner will have no option (75% decide to sell) or will it be restricted to multi unit complexes only  

See;  http://www.abc.net.au/news/2015-09-11/homeowners-could-be-forced-to-sell-properties-under-property-law/6769942 

Edit:   It is the developers that are pushing for this and I could see where a lot of strata owner investors who are renting out their units could be enticed to vote for the sale of a building if the price was right, with no regard for those who live there, tipping the scales in favour of the developer.