Note 12 - Segments - Capital Expenditures by Reportable Segment (Details) - USD ($)	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Capital expenditures and tenant improvements	$ 2,510,152	$ 5,182,033
Acquisition of operating properties	8,996,248	6,116,035
Total real estate investments	11,506,400	11,298,068
Office/Industrial Properties [Member]
Capital expenditures and tenant improvements	2,501,075	5,161,786
Model Home Properties [Member]
Acquisition of operating properties	8,996,248	6,116,035
Retail Properties [Member]
Capital expenditures and tenant improvements	$ 9,077	$ 20,247