My biggest questions are:Should the 12 rentals continue to be kept under a trust?

Then, continue to flip it, but invest your profit (only) in your rentals.Buying rentals is "spending" your money. 

Making some money on the side while doing this would be fantastic, but I'm more concerned about the education to be gained from the opportunity.My rough plan is to gain enough experience to become a wholesaler myself, and use the profits from that to jump into REI (Single-Family homes and Multi-Units) with a strong foundation.I'm currently residing in Cumberland County, more specifically the Vineland/Millville area.

You'll need a solid educational foundation before you start.In the meantime, either get involved in real estate or business in some form.

You have to think what would the borrower do, continue paying a house that is $20k+ upside down at higher than rent values or stop paying, let you foreclose, live free for a year+ during the redemption then go rent a place for $600. 

I don't currently have the capital so I'm spending my time educating myself and saving every dime and investing what I save to multiply it.

Mahalo, much continued success. 

At this point I’m focusing on education and my finances as I work a full time job as a registered nurse (9-530 M-F) and want to be smart about this. 

Be persistent, and continue to learn. 

Instead I would suggest you continue to learn as much as possible.