When I buy stocks, I buy them at what I believe is lower than their long term value is. I also like stocks with dividends. Why? Because if the market tanks, I'm still getting paid.
A loved one is selling his house. His agent told him that almost all buyers will have either a home inspection or a financing clause. Why? Because that is their "out", a way for them to leave the deal without losing all of their deposit.
When we bought our house, we bought it in an established neighborhood (easier to resell than a new development) and negotiated down to a low price. We also bought a house where we could rent out the basement. Why? Because if worst comes to worst, we could and still keep the house.
When people get into trouble, financially or often otherwise, it is usually because they've painted themselves into a corner. They only have one possible satisfactory solution to their situation and if that doesn't happen… well, trouble-funk.
Always have an out. Always have an exit. And keep an eye on that exit.