$400,000 To flip or to brrrr? Or both?

[Sarah DeMamiel]

I have $400,000 to invest for my mother. She is older and would like to have an opportunity to have higher returns on her money at this point in her life. We were initially looking to flip homes, which would potentially bring higher immediate cash returns for her enjoyment in her later years, however I’ve been researching the brrrr method as well to generate cash flow without the stress that flip process may cause her. Supplementing her SS with rental cash flow income may be enough for her to go enjoy life to the fullest AND leave the legacy for her kids and grandkids after she’s gone (that’s also very important to her). 
any thoughts, experiences and nuggets of wisdom are welcomed!