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INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Mortgage Maturities) (Details) - USD ($)	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021	May 31, 2018	Oct. 13, 2016
Annual maturities of mortgage debt
2023-current maturities	$ 8,479,000
2024	2,719,000
2025	3,082,000
2026	21,870,000
2027	6,501,000
Thereafter	372,559,000
Total	415,210,000
Less: unamortized deferred financing costs	(3,310,000)
Secured Debt	$ 411,900,371	$ 370,481,390
Weighted average interest rate (as a percent)	3.97%
Effective interest rate (as a percent)	4.03%
Investment Properties
Annual maturities of mortgage debt
2023-current maturities	$ 226,376
2024	235,293
2025	17,144,563
2026	10,254,197
2027	264,211
Thereafter	138,601,021
Total	166,725,661
Less: unamortized deferred financing costs	(577,253)
Secured Debt	166,148,408		$ 166,256,898
Hamilton Essex 81
Annual maturities of mortgage debt
2026	10,000,000
Total	10,000,000
Less: unamortized deferred financing costs	(44,814)
Secured Debt	9,955,186		9,941,396
345 Franklin
Annual maturities of mortgage debt
2023-current maturities	226,376
2024	235,293
2025	244,563
2026	254,197
2027	264,211
Thereafter	7,601,021
Total	8,825,661
Less: unamortized deferred financing costs	(39,951)
Secured Debt	8,785,710		8,996,847
Hamilton Minuteman
Annual maturities of mortgage debt
Thereafter	6,000,000
Total	6,000,000
Less: unamortized deferred financing costs	(75,357)				$ (123,000)
Secured Debt	5,924,643		5,916,460
Hamilton on Main Apts
Annual maturities of mortgage debt
2025	16,900,000
Total	16,900,000
Less: unamortized deferred financing costs	(34,778)
Secured Debt	16,865,222		16,849,171
Dexter Park
Annual maturities of mortgage debt
Thereafter	125,000,000
Total	125,000,000
Less: unamortized deferred financing costs	(382,353)
Secured Debt	$ 124,617,647		$ 124,553,024	$ 82,000,000