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RENTAL PROPERTIES (Details) |  |  |  |  |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 14, 2022 USD ($) | Oct. 04, 2022 | Jun. 16, 2022 USD ($) property | Nov. 30, 2021 USD ($) property | Mar. 31, 2020 USD ($) | Mar. 31, 2020 USD ($) | Dec. 31, 2022 USD ($) item property | Dec. 31, 2021 USD ($) property | Dec. 31, 2020 USD ($) property | Jun. 15, 2022 property
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 400,703,910 | $ 400,588,242 |  |
Less: Accumulated depreciation |  |  |  |  |  |  | (159,627,479) | (149,233,040) |  |
Total fixed assets, net |  |  |  |  |  |  | 241,076,431 | 251,355,202 |  |
Payment of debt |  |  |  |  |  |  | 2,283,733 | 2,294,389 | $ 2,212,019 |
Mortgage prepayment penalties |  |  | $ 834,544 | $ 2,745,979 |  |  |  |  |  |
Proceeds of mortgage notes payable |  |  |  |  |  |  | 41,889,433 | 88,582,856 | $ 3,781,877 |
Line of credit |  |  |  |  |  |  | 0 | 0 |  |
Brookside Associates LLC Residential Apartments Woburn, Massachusetts |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  | 3.53% | 3.53% |  |  |  |
Repayment of loan |  |  |  |  | $ 2,390,000 | $ 2,390,000 |  |  |  |
Closing Costs |  |  |  |  | $ 136,000 | $ 136,000 |  |  |  |
Extending the maturity until October 14, 2032 | Modification agreement with Brookline Bank. |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  | 4.60% |  |  |  |  |  |  |  |
Existing loan amount | $ 5,954,546.14 |  |  |  |  |  |  |  |  |
Interest only term | 2 years |  |  |  |  |  |  |  |  |
Term of debt | 30 years |  |  |  |  |  |  |  |  |
Additional earnout | $ 1,495,453.86 |  |  |  |  |  |  |  |  |
Debt service coverage ratio | 1.35 |  |  |  |  |  |  |  |  |
Threshold percentage of Loan to Value | 65.00% |  |  |  |  |  |  |  |  |
Extending the maturity until October 14, 2032 | Modification agreement with Brookline Bank. | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Variable interest rate spread |  | 1.70% |  |  |  |  |  |  |  |
Master Credit Facility [Member] |  |  |  |  |  |  |  |  |  |
RENTAL PROPERTIES |  |  |  |  |  |  |  |  |  |
Number of properties | property |  |  | 4 | 11 |  |  |  |  |  | 4
Rental properties |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  | 4.33% | 2.97% |  |  |  |  |  |
Payment of debt |  |  | $ 37,065,000 | $ 65,305,000 |  |  |  |  |  |
Mortgage prepayment penalties |  |  | 834,000 | 2,700,000 |  |  |  |  |  |
Proceeds of mortgage notes payable |  |  | $ 42,404,000 | 89,000,000 |  |  |  |  |  |
Line of credit |  |  |  | $ 89,000,000 |  |  |  |  |  |
Master Credit Facility [Member] | Modification agreement with Brookline Bank. |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) | 4.60% |  |  |  |  |  |  |  |  |
Existing loan amount | $ 5,954,546.14 |  |  |  |  |  |  |  |  |
Interest only term | 2 years |  |  |  |  |  |  |  |  |
Term of debt | 30 years |  |  |  |  |  |  |  |  |
Additional earnout | $ 1,495,453.86 |  |  |  |  |  |  |  |  |
Debt service coverage ratio | 1.35 |  |  |  |  |  |  |  |  |
Threshold percentage of Loan to Value | 65.00% |  |  |  |  |  |  |  |  |
Master Credit Facility [Member] | Modification agreement with Brookline Bank. | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Variable interest rate spread | 1.70% |  |  |  |  |  |  |  |  |
Land, improvements and parking lots |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 87,405,897 | 86,887,276 |  |
Land, improvements and parking lots | Minimum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 15 years |  |  |
Land, improvements and parking lots | Maximum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 40 years |  |  |
Buildings and improvements |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 256,035,191 | 253,952,680 |  |
Buildings and improvements | Minimum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 15 years |  |  |
Buildings and improvements | Maximum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 40 years |  |  |
Kitchen cabinets |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 14,347,212 | 16,946,916 |  |
Kitchen cabinets | Minimum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 5 years |  |  |
Kitchen cabinets | Maximum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 10 years |  |  |
Carpets |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 12,047,573 | 12,029,577 |  |
Carpets | Minimum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 5 years |  |  |
Carpets | Maximum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 10 years |  |  |
Air conditioning |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 501,697 | 501,697 |  |
Air conditioning | Minimum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 5 years |  |  |
Air conditioning | Maximum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 10 years |  |  |
Laundry equipment |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 553,140 | 608,271 |  |
Laundry equipment | Minimum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 5 years |  |  |
Laundry equipment | Maximum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 7 years |  |  |
Elevators |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 1,885,265 | 1,885,265 |  |
Elevators | Minimum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 20 years |  |  |
Elevators | Maximum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 40 years |  |  |
Swimming pools |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 1,090,604 | 1,090,604 |  |
Swimming pools | Minimum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 10 years |  |  |
Swimming pools | Maximum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 30 years |  |  |
Equipment |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 18,716,758 | 18,072,761 |  |
Equipment | Minimum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 5 years |  |  |
Equipment | Maximum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 30 years |  |  |
Motor vehicles |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 171,519 | 171,519 |  |
Useful Life |  |  |  |  |  |  | 5 years |  |  |
Fences |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 46,872 | 46,872 |  |
Fences | Minimum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 5 years |  |  |
Fences | Maximum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 15 years |  |  |
Furniture and fixtures |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  | $ 7,902,182 | 7,898,163 |  |
Furniture and fixtures | Minimum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 5 years |  |  |
Furniture and fixtures | Maximum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 7 years |  |  |
Smoke alarms |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Total fixed assets |  |  |  |  |  |  |  | $ 496,641 |  |
Smoke alarms | Minimum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 5 years |  |  |
Smoke alarms | Maximum |  |  |  |  |  |  |  |  |  |
Rental properties |  |  |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  | 7 years |  |  |
Wholly owned properties |  |  |  |  |  |  |  |  |  |
RENTAL PROPERTIES |  |  |  |  |  |  |  |  |  |
Number of properties | property |  |  |  |  |  |  | 29 |  |  |
Investment Properties |  |  |  |  |  |  |  |  |  |
RENTAL PROPERTIES |  |  |  |  |  |  |  |  |  |
Number of units | property |  |  |  |  |  |  | 690 | 690 | 865 |
NERA 40% |  |  |  |  |  |  |  |  |  |
RENTAL PROPERTIES |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  |  |  | 40.00% | 40.00% | 40.00% |
NERA 50% |  |  |  |  |  |  |  |  |  |
RENTAL PROPERTIES |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  |  |  | 50.00% | 50.00% | 50.00% |
Residential and mixed-use properties | Wholly owned properties |  |  |  |  |  |  |  |  |  |
RENTAL PROPERTIES |  |  |  |  |  |  |  |  |  |
Number of units | item |  |  |  |  |  |  | 2,892 |  |  |
Number of properties | property |  |  |  |  |  |  | 25 |  |  |
Residential and mixed-use properties | Partially owned properties |  |  |  |  |  |  |  |  |  |
RENTAL PROPERTIES |  |  |  |  |  |  |  |  |  |
Number of units | item |  |  |  |  |  |  | 688 |  |  |
Residential and mixed-use properties | Investment Properties | Partially owned properties |  |  |  |  |  |  |  |  |  |
RENTAL PROPERTIES |  |  |  |  |  |  |  |  |  |
Number of properties | item |  |  |  |  |  |  | 7 |  |  |
Residential and mixed-use properties | Limited Partnerships | Partially owned properties |  |  |  |  |  |  |  |  |  |
RENTAL PROPERTIES |  |  |  |  |  |  |  |  |  |
Number of properties | item |  |  |  |  |  |  | 7 |  |  |
Residential and mixed-use properties | NERA 40% | Partially owned properties | Minimum |  |  |  |  |  |  |  |  |  |
RENTAL PROPERTIES |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  |  |  | 40.00% |  |  |
Residential and mixed-use properties | NERA 50% | Partially owned properties | Maximum |  |  |  |  |  |  |  |  |  |
RENTAL PROPERTIES |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  |  |  | 50.00% |  |  |
Condominium | Wholly owned properties |  |  |  |  |  |  |  |  |  |
RENTAL PROPERTIES |  |  |  |  |  |  |  |  |  |
Number of units | item |  |  |  |  |  |  | 19 |  |  |
Number of properties | property |  |  |  |  |  |  | 1 |  |  |

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