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INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Mortgage Maturities) (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	May 31, 2018
Annual maturities of mortgage debt
Secured Debt	$ 370,481,390	$ 283,444,533
Weighted average interest rate (as a percent)	3.91%
Effective interest rate (as a percent)	3.97%
Investment Properties
Annual maturities of mortgage debt
2022-current maturities	$ 222,044
2023	230,792
2024	17,139,883
2025	10,249,333
2026	259,156
Thereafter	138,734,404
Total	166,835,612
Less: unamortized deferred financing costs	(631,905)
Secured Debt	166,203,707	166,308,029	$ 166,404,256
Hamilton Essex 81
Annual maturities of mortgage debt
2025	10,000,000
Total	10,000,000
Less: unamortized deferred financing costs	(51,709)
Secured Debt	9,948,291	9,934,502	9,920,713
345 Franklin
Annual maturities of mortgage debt
2022-current maturities	222,044
2023	230,792
2024	239,883
2025	249,333
2026	259,156
Thereafter	7,734,404
Total	8,935,612
Less: unamortized deferred financing costs	(43,281)
Secured Debt	8,892,331	9,099,301	9,298,174
Hamilton Minuteman
Annual maturities of mortgage debt
Thereafter	6,000,000
Total	6,000,000
Less: unamortized deferred financing costs	(79,448)
Secured Debt	5,920,552	5,912,368	5,904,185
Hamilton on Main Apts
Annual maturities of mortgage debt
2024	16,900,000
Total	16,900,000
Less: unamortized deferred financing costs	(42,803)
Secured Debt	16,857,197	16,841,145	16,825,094
Dexter Park
Annual maturities of mortgage debt
Thereafter	125,000,000
Total	125,000,000
Less: unamortized deferred financing costs	(414,664)
Secured Debt	$ 124,585,336	$ 124,520,713	$ 124,456,090	$ 82,000,000