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INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Mortgage Maturities) (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	May 31, 2018
Annual maturities of mortgage debt
Secured Debt	$ 283,444,533	$ 281,771,246
Weighted average interest rate (as a percent)	3.91%
Effective interest rate (as a percent)	3.98%
Investment Properties
Annual maturities of mortgage debt
2021-current maturities	$ 213,629
2022	222,044
2023	230,791
2024	17,139,883
2025	10,249,333
Thereafter	138,993,558
Total	167,049,238
Less: unamortized deferred financing costs	(741,209)
Secured Debt	166,308,029	166,404,256	$ 166,492,692
Hamilton Essex 81
Annual maturities of mortgage debt
2025	10,000,000
Total	10,000,000
Less: unamortized deferred financing costs	(65,498)
Secured Debt	9,934,502	9,920,713	9,906,924
345 Franklin
Annual maturities of mortgage debt
2021-current maturities	213,629
2022	222,044
2023	230,791
2024	239,883
2025	249,333
Thereafter	7,993,558
Total	9,149,238
Less: unamortized deferred financing costs	(49,937)
Secured Debt	9,099,301	9,298,174	9,489,257
Hamilton Minuteman
Annual maturities of mortgage debt
Thereafter	6,000,000
Total	6,000,000
Less: unamortized deferred financing costs	(87,632)
Secured Debt	5,912,368	5,904,185	5,896,001
Hamilton on Main Apts
Annual maturities of mortgage debt
2024	16,900,000
Total	16,900,000
Less: unamortized deferred financing costs	(58,855)
Secured Debt	16,841,145	16,825,094	16,809,043
Dexter Park
Annual maturities of mortgage debt
Thereafter	125,000,000
Total	125,000,000
Less: unamortized deferred financing costs	(479,287)
Secured Debt	$ 124,520,713	$ 124,456,090	$ 124,391,467	$ 82,000,000