That's great advice, Rocky. After a very long stretch of time being fully rented, my wife and I just had 6 vacancies in a 2-month span that we've (mostly her) had to do deferred maintenance on, find new tenants for, etc. Having enough money set aside (we did) for an unexpected wave of expenses like that is very important. It shouldn't scare any one from buying rentals, but it is a necessary part of Real Estate business planning.
Everyone reading this should ask themselves if they could weather the storm if 1/3 of their rentals were suddenly vacant and stayed that way for 3 months. If not, you better start saving up now!
Robin