Your irresistible offer appears to not have turned out so well either by your own admission and my advice is to help you and others reading this about the importance of knowing how and what to have in your contracts, how to properly vet buyers BEFORE you bring them a deal, etc. your situation is a great learning lesson for others and for yourself if you are willing to learn from your own mistakes.As to the assignment being legal or not, I am not 100% knowledgeable on NC laws, however, I have had several experienced investors tell me North C has similar laws regarding this process as does CA, FL, etc.

The key to having great financial systems is the setup and systems: If you get everything structured properly up front, you avoid most of the ugly problems many RE investors face later on.I'm not an accountant nor a bookkeeper, but I have great recommendations for both!

YOU did not screen property  May be I did not screen properly.

Take ownership of your mistake and learn to do the proper due diligence recommended above😊

He will be required to have references and proper insurance but it's not difficult having him approved. 

I find this level of underwriting lacking with many flippers as well, failing to properly consider the holding costs, insurance costs, taxes, etc.

Were they properly screened?

Partly for the strong casflow that we enjoy after 30+ years investing along with other reasons.I would probably not buy additional property all cash, but improvements and betterments will be paid in cash or at least quickly.Leverage is a great tool when used properly. 

Do you have the knowledge and insight to handle any LT complaints and are you set up properly with your bank and security accounts and can easily collect the rent, etc?

I am focusing instead on how paying down more principal can increase my equity.What am I not considering or putting too little/too much weight on?