Of the 5 homes, I have mortgages on the 2 most expensive ones (we live in one of them). The other 3 I bought more or less cash.
The first condo I bought by selling most of my stock investments. After buying the condo I started investing again. The following year I took out a HELOC out the next condo, sold all my stocks again and bought the next one cash. I did the same for the one after that. I've since paid off the HELOCs.