Their combined monthly income is 3X my rental amount but the man's income is in cash (he is a car mechanic).

To qualify, taxpayers must meet specific criteria demonstrating that they are real estate professionals who materially participate in their rental activities.How to Navigate the Rules:Step 1: Identify your real property trades or businessesHere is a list of activities that are considered to be a real property trade or business:RedevelopmentLeasingConversionConstructionReal property developmentReconstructionOperationRentalBrokerageManagementAcquisitionIf you participate in multiple of these activities, you may be able to combine them making it easier to meet the material participation hour requirements.Step 2: Demonstrate material participation in real property trades or businessesThere are seven tests to determine if you demonstrate material participation.

While all the posts have at lease some legitimate points, I personally believe camp 1 is missing the opportunities present to protect assets under US law mostly because they don’t either understand asset protection, or don’t want to bother with it, so rather than do a proper evaluation they dismiss it as something that won’t work to justify their unwillingness to entertain the idea.Camp 2 is deluding themselves - which delusion has been enhanced by charlatans writing books, giving seminars, and selling packaged plans all of which either attempt to hide your assets or hide the ownership of your assets.  

For example, I'd like to see a sponsor making $150,000 - $300,000 in base salary income from their combined portfolio of projects, if they are managing my money full-time.

Thank you yes that make sense, inclining towards using a combination of free sites and select one paid site like FF, in fact I am looking similar to you for 3 months minimum stay and yes, rooms are furnished.

It combines the pride of owning a tangible asset with the potential for value growth.

As for combining income that gets a bit more tricky. 

Combining these strategies often gives investors the best balance of cost, simplicity, and security.

@Jonathan D. great goals, make sure you combine action and education everyday!

Depending on your goals you could either:1) Cashout refinance and invest proceeds in additional purchases2) Sell or 1031-X them into bigger acquisitions3) Combination of both 1 & 2.