Network with a knowledgeable real estate agent in that area who can point you in the right direction....then have him be the listing agent in exchange for him sharing his expertise.

You will expose yourself to a wider pool of expertise which is critical for real estate investors.Many of us service clients all over the US and even world.

Anyone know if this will protect me if he or one of his guys gets hurt doing my roof?

I have no expertise in personal property only real property so don't do as I suggested.

How should this be structured so that all parties are protected?

To build anything you build from the ground up, begin digging the footings in your education and knowledge, pay attention to the framework, surround yourself with those smarter than you in their fields of expertise.

Yes, I realize that a decent tort attorney is going to be able to pierce your LLC and get to your personal assets in the event of some egregious negligence on your part related to these properties, but there is still a modicum of protection afforded to you with them in an LLC that is not afforded to you when they are titled to you as an individual.My other suggestion would be to talk to a CPA and a decent Business Attorney or Estate Planning Attorney (or both Attorney's) and determine based on your overall individual picture which is the very best way to hold your REI portfolio moving forward. 

But being in a "covered" position gave me some protection.  

Thank you for being so generous with your expertise.

Its usually best to leave the flooring for last (unless you take the time and material to cover it with paper to protect the new installation.)