If the numbers make more sense on the 6 unit, then maybe look into selling your duplex and doing a 1031. 

The mortgage company gets paid off first, then in a traditional sale, the rest minus agent fees and utilities and closing costs goes to the seller.

We have a balance of 266K on the mortgage @ 3 percent interest.

Lots of the properties I looked at were not treated nicely by the tenants. 

Welcome to the community, Sean! 

I am an aspiring real estate investor, excited to dive into the world of property flipping.

What is the ARV?

@Stuart Udis my thought was to spread the risk is why to partner.

Partnering with a wholesaler sounds fine, but check the real estate licensing laws in your state before bringing a buyer for a commission.You might consider getting your real estate agent's license and legitimately earn what your skills, drive, and experience truly command. exactly wholesaling or bird dogging is not a life time or long time occupation  RE sales can be lifetime and if your any good at it at about year 10 you should be getting all your sales from referrals and such.

You'd need to call the local township which I would recommend doing for any LTBH.