hurry buyers time to buy or you will be sorry, page-44

I suppose if the rental property is owned outright, it can sit there, empty, with minimum cost to the owner (forget ownership costs and potential lost revenue from trapped capital for the moment). But if it is subject to mortgage/loan repayments etc... then it can be quite costly to not have a tenant. And if the "good tenant" loses employment, well good luck evicting them before they kick holes in the walls and smear shit into the carpet.
Summary. If you think you are going to get rich sitting on your ass extracting rent...be careful. the idea is not new/ has been tried before. Works for some not all. And may I add...the top richest from property got rich selling property... not buying. be warned