All depends on your investment strategy. If you're using neutral...

All depends on your investment strategy. If you're using neutral or positively geared properties than 20 is achievable. If you have negatively geared properties than that is where people are going to start running into problems if there is a bust/interest rate hikes. 60% of people who are negative gearing earn $80,000 or less and these are the people that will have serious trouble if repayments go up. Doesn't mean that negative gearing is a bad idea you just have to do what works for your situation.