MORTGAGE NOTES PAYABLE (Facility Agreement Properties) (Details) - Facility Agreement - USD ($)	Nov. 30, 2021	Nov. 29, 2021
Debt Instrument [Line Items]
Mortgage amount	$ 156,000,000	$ 65,305,000
Deferred Finance Costs	1,676,088
Mortgage prepayment penalties	2,700,000
Clovelly Apartments L.P. Residential Apartments Nashua, New Hampshire
Debt Instrument [Line Items]
Mortgage amount	11,214,000	4,160,000
Deferred Finance Costs	121,817
Mortgage prepayment penalties	167,141
Commonwealth 1137 L.P. Residential Apartments Boston, Massachusetts
Debt Instrument [Line Items]
Mortgage amount	5,440,000	3,750,000
Deferred Finance Costs	60,504
Mortgage prepayment penalties	151,314
Commonwealth 1144 L.P. Residential Apartments Boston, Massachusetts
Debt Instrument [Line Items]
Mortgage amount	32,325,000	14,780,000
Deferred Finance Costs	340,007
Mortgage prepayment penalties	592,728
Executive Apartments L.P. Residential Apartments Framingham, Massachusetts
Debt Instrument [Line Items]
Mortgage amount	8,190,000	2,415,000
Deferred Finance Costs	89,333
Mortgage prepayment penalties	96,434
North Beacon 140 L.P. Residential Units Boston, Massachusetts
Debt Instrument [Line Items]
Mortgage amount	12,683,000	6,937,000
Deferred Finance Costs	135,813
Mortgage prepayment penalties	277,003
Olde English Apartments L.P. Residential Apartments Lowell, Massachusetts
Debt Instrument [Line Items]
Mortgage amount	9,608,000	3,080,000
Deferred Finance Costs	104,345
Mortgage prepayment penalties	123,956
Redwood Hills L.P. Residential Units Worcester, Massachusetts
Debt Instrument [Line Items]
Mortgage amount	17,105,000	6,743,000
Deferred Finance Costs	188,406
Mortgage prepayment penalties	271,204
River Drive L.P. Residential Apartments Danvers, Massachusetts
Debt Instrument [Line Items]
Mortgage amount	9,543,000	3,465,000
Deferred Finance Costs	104,605
Mortgage prepayment penalties	139,218
Highland Street Apartments, L.P. Residential Apartments Lowell, Massachusetts
Debt Instrument [Line Items]
Mortgage amount	3,960,000	1,050,000
Deferred Finance Costs	45,076
Mortgage prepayment penalties	41,928
WCB Associates LLC Residential Apartments Brockton, Massachusetts
Debt Instrument [Line Items]
Mortgage amount	19,266,000	7,000,000
Deferred Finance Costs	204,586
Mortgage prepayment penalties	408,873
Hamilton Oaks Associates LLC Residential Apartments Brockton, Massachusetts
Debt Instrument [Line Items]
Mortgage amount	26,666,000	$ 11,925,000
Deferred Finance Costs	281,596
Mortgage prepayment penalties	$ 476,180

Face (par) amount of debt instrument at time of issuance.

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