LLC is best, it defines member responsibilities, distribution etc.

I 100% believe that if you want to treat it like a large distributed portfolio you could even start to get some contractor discounts, etc.

The tax benefit to an S-Corp is that you may be able to reduce self-employment tax on a portion of the profits by paying yourself a distribution instead of a salary. 

I own a lighting distribution and manufacturing company and have seen the transition first hand. 

Is this the technique that investors use when group funding larger commercial deal too?

If you guys have any good techniques to finding local investment partners in the Los Angeles and San Fernando Valley areas that would be awesome and I would really appreciate anything your willing to share.

I'd get him to sign an addendum that gives you the power to sell the properties/deeds them to you and lays out distribution of funds.

When the estate is administered his interest in the LLC will need to be distributed in accordance with the Trust agreement (if it was held by the trust you referenced) or according to his will.If there are assets outside of the LLC if your mom is the executrix and should administer the estate in accordance with the will.  

They include photography, yard sign, lock box, MLS listing, and promotion through the usual 30 or so distribution sites, and have up-sales of running an open house and a few others.  

Manufacturing and/or distribution of a controlled substance is a deny.