They even have a value add less than performing a garage conversion.  

That market from what I can see on the few trips I made to perform due diligence is really robust and such a pretty area I can see the attraction for those working in Tech or govmit in DC. 

Books are important to maintain because it keeps track of the performance of the partnership not only for one year but over several years.Partners normally have the right to inspect the books.Will the accountant you work with either maintain the books for you or help you make sure its done correctly?

I agree with @Chris Seveney that a performing note would be a very good starting point.

We bought the property seller-financed with power, a small bathroom/laundry building, a 40x60 metal shop building, an RV pad with 'full hookups' (power, water, septic) and not much else.  

Small multifamily, up to 4 units (at least to start), then graduate into larger investments as your portfolio performs positively. 

Quote from @Jonathan Greene: Never sell a high-performing property with no cap ex and low maintenance to buy another rental.

In fact many properties being shopped around by wholesalers are actually just expired MLS listings (properties that failed to sell on the MLS) or active MLS listings under contract by a wholesaler. 

They don't guarantee their performance and your money is lost if they flee with it. 4.

Make sure you don't chase deals where you can't perform.