This has risks in controlling the amounts you abate translating directly into the amounts they capitalize in repairs.  

Remember you don't have to own a property to control it.

Not to say that people aren't somewhat responsible but there are some factors out of people's control.

There are plenty of folks who stay away from condos because of the lack of direct control due to the HOA but if it's a larger complex with stable management and a businesslike approach to capex and maintenance I think you could do fine.

Year to year you can't control the rising expense of a flood insurance.

When the son gets to the point he "controls/owns" the property, he can refinance. 

And, I controlled my business, didn't have to do anything I didn't like.

The way it is structured you have all of the experience and he has all of the control as the two smaller investors have no control, by that I mean your two votes don't outweigh his ownership- when is it time to sell, replace the roof, raise the rent, evict a tenant, etc. 

Mark when I talk to the real estate acquisitions and development managers for the area for those companies the NUMBER ONE question they will have is are you the owner, the listing broker, or do you have the property under contract and CONTROL??

Remember you don't have to own a property to control it.Download BP’s newest book here some good due diligence in Chapter 10.