There is no right to debt. Banks can and do change their views on sectors, segements, LVR's, security depending on the state of the market. After al, it is their money they are putting at risk (and mine, given I own shares in ANZ).
The reality is that they are tightening now, given Australia has some of the most expensive real estate in the world. Given GFC etc, they are rightly being cautious on lending. So fix it up, provide more security or roll over when they shout "roll over" (LOL).
