1. Never rent to, employ, or go into business with family.
2. Find a smokin deal, do very little work and resell it. When I use to flip properties I learned the the less you do, the less risk and the more you make. Big rehabs are a risky business.
For example, the best flip I ever did was a house that was move in ready when I bought it. We offered a low price, they took it. I then hired a painter to paint the brick on the front of the house. Cost me $200.00. I listed the house and sold it for an $8000 profit.