Strategies or rules of thumb for cash reserves

[Brandon Callahan]

When first starting out and resources/cash flow are limited, what are some good strategies or rules of thumb to ensure that things like vacancies or costly repairs don’t render you unable to pay the loan or mortgage on the property? I’m just starting to learn more about RE investing and I keep thinking, “what if i had 5 empty properties with 5 mortgages all due at once?” Obviously I’m thinking worst case scenario.

Any advice or strategies on how much someone should have in reserves to protect themselves from major repairs or extended vacancies?