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INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Mortgage Maturities) (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	May 31, 2018	Oct. 13, 2016
Annual maturities of mortgage debt
2023-current maturities	$ 8,719,000
2024	31,306,000
2025	11,094,000
2026	21,904,000
2027	6,507,000
Thereafter	293,060,000
Total	372,590,000
Less: unamortized deferred financing costs	(2,619,000)
Secured Debt	$ 369,970,778	$ 370,481,390
Weighted average interest rate (as a percent)	3.91%
Effective interest rate (as a percent)	3.97%
Investment Properties
Annual maturities of mortgage debt
2023-current maturities	$ 224,199
2024	233,032
2025	17,142,212
2026	10,251,753
2027	261,671
Thereafter	138,668,034
Total	166,780,901
Less: unamortized deferred financing costs	(604,578)
Secured Debt	166,176,323		$ 166,282,719
Hamilton Essex 81
Annual maturities of mortgage debt
2026	10,000,000
Total	10,000,000
Less: unamortized deferred financing costs	(48,262)
Secured Debt	9,951,738		9,937,949
345 Franklin
Annual maturities of mortgage debt
2023-current maturities	224,199
2024	233,032
2025	242,212
2026	251,753
2027	261,671
Thereafter	7,668,034
Total	8,880,901
Less: unamortized deferred financing costs	(41,615)
Secured Debt	8,839,286		9,048,329
Hamilton Minuteman
Annual maturities of mortgage debt
Thereafter	6,000,000
Total	6,000,000
Less: unamortized deferred financing costs	(77,402)				$ (123,000)
Secured Debt	5,922,598		5,914,414
Hamilton on Main Apts
Annual maturities of mortgage debt
2025	16,900,000
Total	16,900,000
Less: unamortized deferred financing costs	(38,791)
Secured Debt	16,861,209		16,845,158
Dexter Park
Annual maturities of mortgage debt
Thereafter	125,000,000
Total	125,000,000
Less: unamortized deferred financing costs	(398,508)
Secured Debt	$ 124,601,492		$ 124,536,869	$ 82,000,000