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INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Mortgage Maturities) (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	May 31, 2018	Sep. 12, 2016
Annual maturities of mortgage debt
2024	$ 2,853,000
2025	3,602,000
2026	25,112,000
2027	23,271,000
2028	31,875,000
Thereafter	324,726,000
Total	411,439,000
Less: unamortized deferred financing costs	(2,779,000)
Secured Debt	$ 408,660,292	$ 410,966,199
Weighted average interest rate (as a percent)	4.23%
Effective interest rate (as a percent)	4.29%
Investment Properties
Annual maturities of mortgage debt
2024	$ 17,139,883
2025	10,249,333
2026	259,155
2027	269,365
2028	132,465,039
Thereafter	6,000,000
Total	166,382,775
Less: unamortized deferred financing costs	(413,294)
Secured Debt	165,969,481	166,090,968	$ 166,203,707
Hamilton Essex 81
Annual maturities of mortgage debt
2025	10,000,000
Total	10,000,000
Less: unamortized deferred financing costs	(24,131)
Secured Debt	9,975,869	9,962,080	9,948,291
345 Franklin
Annual maturities of mortgage debt
2024	239,883
2025	249,333
2026	259,155
2027	269,365
2028	7,465,039
Total	8,482,775
Less: unamortized deferred financing costs	(29,963)
Secured Debt	8,452,812	8,676,945	8,892,331
Hamilton Minuteman
Annual maturities of mortgage debt
Thereafter	6,000,000
Total	6,000,000
Less: unamortized deferred financing costs	(63,081)				$ (123,000)
Secured Debt	5,936,919	5,928,736	5,920,552
Hamilton on Main Apts
Annual maturities of mortgage debt
2024	16,900,000
Total	16,900,000
Less: unamortized deferred financing costs	(10,701)
Secured Debt	16,889,299	16,873,248	16,857,197
Dexter Park
Annual maturities of mortgage debt
2028	125,000,000
Total	125,000,000
Less: unamortized deferred financing costs	(285,418)
Secured Debt	$ 124,714,582	$ 124,649,959	$ 124,585,336	$ 82,000,000