This situation is why I don't like the rent by room model and wouldn't use it myself, but some people are very successful at running harmonious co-living arrangements. 

I arrange financing nationwide.

If you haven't signed a contract with them, I would suggest reconsidering this arrangement. 

The Agreement also states that he will be subject to the terms and conditions of the Lease Exhibit A while living in the home.I have two concerns:  1) in this type of arrangement, would I be able to evict him if he defaulted on the payments?

Typically in those types of arrangements when money is coming in the door it goes to the money partner first to lower their balance as you are splitting profits not income. 

Because the 401(k) is an employer plan instead of an Individual Retirement Arrangement, many of the plan-side features are more powerful, such as higher contribution limits, the availability of participant loans, etc.Structurally, you can achieve full checkbook control over either an IRA or a Solo 401(k).  

This is supported by search trends by terms like "affordable apartments Fayetteville NC" and "houses for rent under $500 in Fayetteville NC" suggesting a high demand for cost-effective living arrangements.

Chances are, the living arrangements and property use is not as it was supposed to be.If the money is good, set a lease with extra provisions for the dope house cleanup when the tenant leaves.You can't charge for the plants, but you can charge for uncommon use of the property.

I am not saying they do all of those positions full-time, but to find someone who is capable to do all of those positions successfully and not get burnt out with the current pay expectations it is difficult to achieve regardless of a 3rd party or a sponsorship team being at the helm. 

As a general who does a remodel project for a seller but the arrangement is to get paid at closing.