As an investor, if your tenants will be paying the gas bill, you will be best served by fitting a new tank style water heater that is properly sized for the number of occupants in each unit.  

This is why I teach my team the need to have MULTIPLE LEAD PIPELINES.

Both good answers above, I don't mean to be insulting, but you say you are "teaching" investors.

Key West Style home in a gated community, Bimini Bay. 1 1/2 mile from the bay.

We teach it in our group, and put it into practice.It isn't as simple as "I have C.C.'

I kept searching for one, finally I realized I was wanting someone to not only give me their knowledge they have learned over the years and their time to teach me.

My SFR's were built in the period where Aluminum wiring was used so it depends on your style/age house.The worst I ever had a tenant do?

I know it's repeated often but you have time and I'm sure a talent that an experienced investor needs and would be willing to trade for teaching you the ropes.  

Both can teach you a great deal and having the job could help you with building your credit and capital to effectively dive into the wonderful industry of real estate!

If you're not able to find that kind of position, the next thing I would do is talk to the top managing brokers to see if they will teach you how to succeed and give you connections.