Paid a top local esigner to come have a look and all she did was insult our cute little place that was doing just fine.....But I think where a designer could add value is by suggesting unique areas, like game rooms, coffee bars, outdoor BBQ/play areas, and stuff like that. 

My lawyer suggests in a situation like this that I give them a notice that I am the new owner and that as of a certain date they owe market rent of $X,XXX.

I suggest consulting with a real estate attorney to ensure proper structuring of the LLC/land trust and review the tax and insurance implications.

Is there a alternate way to structure it, please suggest.

If I were to pad the trustworthy broker's suggested ARV by 10%, and the trustworthy contractor's quote by 20%, would you say that I would likely be within realistic range, on average? 

Nathan Roberts also on this site may have some suggestions as well. 

I would suggest you go the commercial route. 

I would suggest getting Dave Ramsey's book called The Total Money Makeover and read that.

If you have specific questions or specific goals, I'm sure the Bigger Pockets Community would have suggestions for you.

The only other question I would suggest is that you do engage a property management company to review your quad and review your monthly financials.