You don't want to start a relationship to learn about storage units and then find out they only invest in single-family homes.3.

There are other neighboring towns in other parts of Essex and Hudson counties that are feasible options as well.I'm an investor and investor-agent based in Northern NJ (Bergen, Hudson, Essex, and Passaic counties).

Is this a feasible idea?

Instead of only buying single-family homes, for example, you could invest in multifamily homes, self-storage facilities, and mobile homes.

So was just curious if this was even feasible for us in the future

While both are dependent on the bank / lender, getting a HELOC on an owner occupied loan is more feasible than getting one on an investment property.

Are you looking for a specific niche, such as self storage or multifamily?

Some states do not allow RUBs due to the inherit unfairness of the allocation of the apartments' W&S  expenses .Although sometimes not economically feasible in older properties, water sub-metering is practically unanimously accepted through the US.

Some of the best skills I've learned are basic real estate math and finance —being able to analyze potential deals to see if they are feasible and can generate good profit or cash flow. 

In my case, I have residential rentals in one LLC, commercial properties in another, self storage in a third, and my real estate company operates in a fourth.