Investing after a payout

Hello I feel I should give some background as it will help out my position into context.

1. I received a compo payout after a car accident.
2. During the GFC I organised a loan to parents so they could keep a business running and not lose their house. My money went to their mortgage offset.
3. They have since paid back all of the capital, however by the end of the year, in due to receive 500K in interest.

I understand the 500k amount will be subject to tax. I'm on just over 100k p.a as a teacher and have recently separated from the wife. I pay child support etc too. I am hoping to build wealth through investing in property and have done some research on where to start with the money comes in but my worst case scenario is I'll loose a large part of that 500k in tax.

What would you do in my position?

P.S I hope this makes sense!