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INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Mortgage Maturities) (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	May 31, 2018	Sep. 12, 2016
Annual maturities of mortgage debt
2023-current maturities	$ 2,706,000
2024	2,861,000
2025	3,613,000
2026	25,081,000
2027	23,251,000
Thereafter	356,613,000
Total	414,125,000
Less: unamortized deferred financing costs	(3,159,000)
Secured Debt	$ 410,966,199	$ 370,481,390
Weighted average interest rate (as a percent)	4.15%
Effective interest rate (as a percent)	4.21%
Investment Properties
Annual maturities of mortgage debt
2023-current maturities	$ 230,791
2024	17,139,883
2025	10,249,333
2026	259,155
2027	269,364
Thereafter	138,465,041
Total	166,613,567
Less: unamortized deferred financing costs	(522,599)
Secured Debt	166,090,968	166,203,707	$ 166,308,029
Hamilton Essex 81
Annual maturities of mortgage debt
2025	10,000,000
Total	10,000,000
Less: unamortized deferred financing costs	(37,920)
Secured Debt	9,962,080	9,948,291	9,934,502
345 Franklin
Annual maturities of mortgage debt
2023-current maturities	230,791
2024	239,883
2025	249,333
2026	259,155
2027	269,364
Thereafter	7,465,041
Total	8,713,567
Less: unamortized deferred financing costs	(36,622)
Secured Debt	8,676,945	8,892,331	9,099,301
Hamilton Minuteman
Annual maturities of mortgage debt
Thereafter	6,000,000
Total	6,000,000
Less: unamortized deferred financing costs	(71,264)				$ (123,000)
Secured Debt	5,928,736	5,920,552	5,912,368
Hamilton on Main Apts
Annual maturities of mortgage debt
2024	16,900,000
Total	16,900,000
Less: unamortized deferred financing costs	(26,752)
Secured Debt	16,873,248	16,857,197	16,841,145
Dexter Park
Annual maturities of mortgage debt
Thereafter	125,000,000
Total	125,000,000
Less: unamortized deferred financing costs	(350,041)
Secured Debt	$ 124,649,959	$ 124,585,336	$ 124,520,713	$ 82,000,000