What if you don't find tenants, does it make sense to buy a rental property then?

Hi : 

You do not have to purchase an apartment if you do not have a ready tenant or a a shortage of units  in the market.Selecting a tenant is the most crucial decision when it comes to screen a tenant. if your rental apartment bring 8-10% profit a year, and a tenant misses 1 payment a year this is a 8.33 % loss if you are taking a 90% LTV loan from the bank. 

Good Luck 

You can still exit the investment through a re-sale. Tenancy is not the only way to profit.