The BRRR strategy gets talked about a lot in real estate, it's simple on paper, kind of like the saying of "buy low, sell high", except that you never sell and just keep taking out more loans against your assets. Some people see that as risky as you could end up underwater in a downturn. In this article I explain how to mitigate that risk.
https://investomation.com/blog/brrr-a-cool-strategy-for-hot-markets