REAL ESTATE INVESTMENTS - Portfolio Concentrations (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Real Estate [Line Items]
Total Investment in Real Estate Property, Net	$ 224,648,345	$ 135,235,616
Total revenues	17,984,625	7,390,206
Net Carrying Value	238,924,160	149,759,638
AvAir, AZ
Real Estate [Line Items]
Total revenues	$ 2,670,159	$ 2,100,000
Percentage of Total Assets	14.80%	19.90%
AvAir, AZ \| Percentage of Total Assets
Real Estate [Line Items]
Total Investment in Real Estate Property, Net	$ 26,634,909	$ 27,353,125
Percentage of Total Assets	10.60%	17.40%
Costco \| Percentage of Total Assets
Real Estate [Line Items]
Total Investment in Real Estate Property, Net	$ 29,974,716	$ 0
Percentage of Total Assets	11.90%	0.00%
Northrop Grumman
Real Estate [Line Items]
Total revenues	$ 0	$ 1,162,274
Percentage of Total Assets	0.00%	11.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Amount of real estate investments, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; (7) other real estate investments; (8) real estate joint ventures; and (9) unconsolidated real estate and other joint ventures not separately presented.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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