Note 4 - Real Estate Assets - Future Minimum Rental Revenues (Details)	Dec. 31, 2019 USD ($)
Office/Industrial and Retail Properties [Member]
2020	$ 16,907,553
2021	13,535,430
2022	10,425,658
2023	7,043,128
2024	5,336,123
Thereafter	5,428,467
Totals	58,676,359
Model Home Properties [Member]
2020	3,016,320
2021	1,047,924
Totals	$ 4,064,244

Amount of lease payments to be received by lessor for operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919396-209981

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Amount of lease payment to be received by lessor for operating lease in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of lease payment to be received by lessor for operating lease in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lease payment to be received by lessor for operating lease in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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