My business partner and I are closing on a condo in the next couple of weeks that needs a major rehab. 

Could be a U.S. citizen with a SSN who also has tax identification number for their business, an EIN (Employer Identification Number).

Raise there rent to market if you are operating a business, give them a discount under market, if you are operating a charity.

you should do a phase one as a matter of course on any property you buy that is of significant value. its just smart and good insurance to make sure you don't have any environmental hazards.. just cost of doing business.

Your time (both personal and business related) becomes more valuable than the cost you incur to hire others to do some of the work.

Luckily we live in a business friendly state that makes this information accessible for the researched business owner.

What potential pitfalls could arise in this type of business model (other than check your local and state ordinances, thats obvious)Any advice would be very helpful. 

Learn to prospect and you will learn to build your own business.

Whatever he owns in the LLC should be protected though, if he/you maintained properly the LLC.If one of the other partners in the LLC get in trouble, depending on how the LLC partnership is created, the LLC assets (that joint account...is that a business account?)

I learned I am not a great business person I have the creative hustle needed to put deals together but lack the follow through to keep them coming in.