@Allen Yeung Options can be great or a weight can't they? 

Pro: Rapidly increase savings.

With that much rapid growth, I can't imagine there isn't also some other optimizing that could be done - renovating kitchens between tenants to maximize rent, that sort of thing.

A brick house is going to be more due to the weight of brick being heavier than siding.Depends on the size of the house you are demoing.

Even though it doesn't mean a whole lot, outsiders give a lot of weight to formal structure

Now that interest rates are going up rapidly (~5-6% at the time of this post), would it be even more appealing to use a HELOC if I can keep my 3.1% fixed 30-year mortgage and plan to hold the property for the long term?

What happens when someone refuses to carry their weight or steals your leftover pizza from the fridge?

But all the high leverage antics, do yourself a favor and forget that BS, it's a fast track to NEVER getting into REI, just getting in to rapidly loose it all and then some.

Currently 16 SFH in Cedar Rapids. 

Hello @Eddy Tijerina,My recommendation is If the property is situated in a market that has experienced long-term rapid appreciation and rent growth, it is advisable to hold onto it.