Reason is a Heloc generally carries a higher rate on a shorter term and "Can Never" be used as an "Asset, or for PITI reserves" which are both required when you buy an investment property. 

Buy quality properties in strong submarkets, finance with low leverage, bulk up on cash reserves, diversify geographically, and you'll be positioned to survive whatever the economy throws at you.

And it's not only the homes, you also have to fortify your grocery stores, schools and anything else.

Clothing- buy at the second hand store.  

I have a 10x8 shed that I use exclusively to store real estate materials and supplies.

This is verified based on the good schools, department stores opening up (Costco, Target etc.) as well as verified investment from Jerry Jones (Dallas Cowboys owner) and the city to grow the population.

Gone are the days prior to 2019 where I as a complete newbie could buy and get instant equity, use financing at sub 5% and still cash flow while maintaining a reserve balance.

I immediately went to the project and took the contractor to the store to buy all of our supplies. 

Also keep reserves beyond your 30k for unexpected issues.

For example, my appliance store gives me a 10% discount, so I charge a 5% markup to my owners to make a little money and the owner still saves 5% from retail.