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The notional percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Details) (USD $)	12 Months Ended			0 Months Ended			1 Months Ended		0 Months Ended	1 Months Ended				0 Months Ended	1 Months Ended			12 Months Ended	1 Months Ended	0 Months Ended				1 Months Ended		3 Months Ended
	Dec. 31, 2014 item	Dec. 31, 2013	Dec. 31, 2012	Oct. 18, 2013	Oct. 28, 2009	Oct. 28, 2009	Oct. 31, 2009	Apr. 30, 2008	Feb. 01, 2015 item	Feb. 28, 2007	Mar. 31, 2005	Sep. 30, 2013	Aug. 31, 2008	Mar. 02, 2005	Oct. 31, 2004	Jan. 31, 2007	Aug. 31, 2014	Dec. 31, 2005 item	Jun. 30, 2013	Dec. 15, 2011	Oct. 02, 2011	Aug. 02, 2011	Aug. 17, 2010	Apr. 30, 2012	Feb. 29, 2012	Dec. 31, 2010	Oct. 03, 2005 item	Mar. 07, 2005	Sep. 30, 2004 item	Dec. 31, 2006	May 31, 2008 item	Aug. 31, 2004 item	Nov. 30, 2001 item	Dec. 31, 2011
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of limited partnerships and limited liability companies in which the entity has invested	9
Number of partnerships investing in commercial property	3
Investments in joint venture	$ 8,807,868us-gaap_EquityMethodInvestments	$ 12,025,142us-gaap_EquityMethodInvestments
Outstanding amount of mortgage loan	196,071,540us-gaap_SecuredDebt	198,520,478us-gaap_SecuredDebt
Interest paid	8,791,000us-gaap_InterestPaid	8,062,000us-gaap_InterestPaid	7,776,000us-gaap_InterestPaid
Gain on Sale of Real Estate		3,678,839
Distribution to the Partnership	3,858,386	3,893,662	3,932,410
Carrying value of investment to discontinue applying the equity method	0
Limited Partnerships
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Distribution to the Partnership	850,000
Dexter Park
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture					15,925,000	15,925,000
Outstanding amount of mortgage loan	86,240,813	87,410,638	88,611,686
Percentage of ownership interest					40.00%	40.00%
Number of units	409	409	409
Purchase price of investments					129,500,000	129,500,000
Investments funded using cash reserves					8,757,000
Capital contributions				660,000
Number of units retained for long-term investment	409	409	409
Gain on Sale of Real Estate	0
Number of units sold	0
Units to be sold	0
Dexter Park \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage loan	86,241,000
Borrowings							89,914,000
Interest rate (as a percent)					5.57%	5.57%
Period for which the entity is required to make interest only payments							2 years
Amortization period of debt						30 years
Hamilton Bay Apartments
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture																											2,500,000
Outstanding amount of mortgage loan	4,574,002	4,639,848	4,702,087
Percentage of ownership interest																											50.00%
Number of units	48	48	48					20																			168
Purchase price of investments																											30,875,000
Number of units retained for long-term investment	48	48	48							48																	48
Gain on Sale of Real Estate	0
Number of units sold	0
Units to be sold	0
Hamilton Bay Apartments \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage loan	4,574,000
Borrowings								2,368,000
Interest rate (as a percent)								5.75%
Hamilton Bay Sales
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage loan	0		1,668,000
Number of units	120	120	120
Number of units retained for long-term investment	0	0
Gain on Sale of Real Estate	475,335
Number of units sold	113	105	105
Units left to sell	7	15	15						7
Units to be sold	120	120	120
Hamilton Bay Sales \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Borrowings										4,750,000
Interest rate (as a percent)										5.57%
Period for which the entity is required to make interest only payments										5 years
Amortization period of debt										30 years
Hamilton Essex Development, LLC and Hamilton Essex 81, LLC
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture																												2,000,000
Percentage of ownership interest																												50.00%
Purchase price of investments																												14,300,000
Hamilton Essex Development, LLC and Hamilton Essex 81, LLC \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Borrowings											10,750,000
Hamilton Essex 81
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage loan	8,109,676	8,234,548	8,352,317
Number of units	49	49	49
Number of units retained for long-term investment	49	49	49
Gain on Sale of Real Estate	0
Number of units sold	0
Units to be sold	0
Hamilton Essex 81 \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Borrowings	8,110,000
Interest rate (as a percent)	5.79%
Amortization period of debt	30 years
Hamilton Essex Development
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage loan	1,987,830	2,041,146	2,093,184
Number of units	1	1	1
Number of units retained for long-term investment	1	1	1
Gain on Sale of Real Estate	0
Number of units sold	0
Units to be sold	0
Hamilton Essex Development \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Borrowings	1,988,000
Contractual principal payments to be made	4,443												4,301
Margin over basis of interest rate (as a percent)	2.25%
Basis of interest rate		Libor
Notional margin over basis of interest rate (as a percent)		0.17%
Cost associated with loan extension												9,000	6,000
Extended term of debt												2 years
Maximum personal guaranty on mortgage													1,000,000
Hamilton 1025
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture														2,352,000
Outstanding amount of mortgage loan	4,806,039	4,869,583	4,934,741
Percentage of ownership interest														50.00%
Number of units	176	176	176											176
Purchase price of investments														23,750,000
Number of units retained for long-term investment	49	49	49											49
Gain on Sale of Real Estate	0
Number of units sold	127	127	127											127
Units to be sold	127	127	127
Hamilton 1025 \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage loan	4,806,000
Borrowings														5,000,000
Interest rate (as a percent)														5.67%
Period for which the entity is required to make interest only payments														5 years
Amortization period of debt														30 years
Term of debt														10 years
Hamilton Minuteman
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture																													5,075,000
Outstanding amount of mortgage loan	5,292,511	5,362,109	5,433,472
Percentage of ownership interest																													50.00%
Number of units	42	42	42																										42
Purchase price of investments																													10,100,000
Number of units retained for long-term investment	42	42	42
Gain on Sale of Real Estate	0
Number of units sold	0
Units to be sold	0
Amount returned to partnership															3,775,000
Hamilton Minuteman \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage loan	5,293,000
Borrowings															8,025,000	5,500,000
Interest rate (as a percent)																5.67%
Period for which the entity is required to make interest only payments																5 months
Amortization period of debt																30 years
Term of debt																10 years
Cash contribution by the entity towards loan																														1,250,000
Hamilton on Main Apts
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture																																8,000,000
Outstanding amount of mortgage loan	16,900,000	15,317,643	15,611,045
Percentage of ownership interest																																50.00%
Number of units	148	148	148																													280
Purchase price of investments																																56,000,000
Number of units retained for long-term investment	148	148	148
Gain on Sale of Real Estate	0
Number of units sold	0																														137
Units to be sold	0
Hamilton on Main Apts \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Borrowings																	16,900,000
Interest rate (as a percent)																	4.34%
Term of debt																	10 years
Hamilton on Main Apartments, LLC \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units																		3
Borrowings																		16,825,000
Interest rate (as a percent)																		5.18%
Period for which the entity is required to make interest only payments																		3 years
Amortization period of debt																		30 years
Term of debt																		10 years
Term excluding period for which interest only payments to be made																		7 years
Net proceeds after funding escrow accounts and closing costs																		16,700,000
Refinanced amount																		15,205,000
Refinancing fees	161,000
345 Franklin
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture	0																																1,533,000
Outstanding amount of mortgage loan	10,000,000	10,000,000	6,850,179
Percentage of ownership interest																																	50.00%
Number of units	40	40	40																														40
Number of units retained for long-term investment	40	40	40
Repayment of loan																			6,776,000
Gain on Sale of Real Estate	0
Number of units sold	0
Units to be sold	0
Carrying value of investment to discontinue applying the equity method																			0
345 Franklin \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage loan	10,000,000
Interest rate (as a percent)																			3.87%
Period for which the entity is required to make interest only payments																			3 years
Amortization period of debt																			30 years
Term of debt																			15 years
Refinanced amount																			10,000,000
Distribution to the Partnership																			1,610,000
Residential buildings \| Dexter Park
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	409	409	409		409	409
Residential buildings \| Hamilton Bay Apartments
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	48	48	48
Residential buildings \| Hamilton Bay Sales
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	120	120	120
Residential buildings \| Hamilton Essex 81
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	48	48	48
Residential buildings \| Hamilton Essex Development
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	0
Residential buildings \| Hamilton 1025
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	175	175	175
Residential buildings \| Hamilton Minuteman
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	42	42	42
Residential buildings \| Hamilton on Main Apts
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	148	148	148
Residential buildings \| 345 Franklin
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	40	40	40
Apartment \| Hamilton Essex Development, LLC and Hamilton Essex 81, LLC
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units																												48
Commercial \| Dexter Park
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	0
Commercial \| Hamilton Bay Apartments
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	0
Commercial \| Hamilton Bay Sales
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	0
Commercial \| Hamilton Essex Development, LLC and Hamilton Essex 81, LLC
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of properties																												1
Commercial \| Hamilton Essex 81
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	1	1	1
Commercial \| Hamilton Essex Development
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	1	1	1
Commercial \| Hamilton 1025
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	1	1	1
Commercial \| Hamilton Minuteman
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	0
Commercial \| Hamilton on Main Apts
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	0
Commercial \| 345 Franklin
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	0
Car parking lot \| Hamilton Essex Development, LLC and Hamilton Essex 81, LLC
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Capacity of real estate property (in cars per lot)																												50
HBC
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage loan																																		1,668,600
Borrowings						7,168,000
Interest rate (as a percent)					6.00%	6.00%
Term of debt						4 years
Notice period for principal paydown of debt						6 months
Repayment of loan																								918,600		2,500,000
Contractual principal payments to be made																				1,000,000	1,000,000	1,000,000			750,000
Interest paid			18,960
Principal amount requested to be repaid																							2,500,000
HBC \| Dexter Park \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Borrowings							$ 7,168,000
Interest rate (as a percent)					6.00%	6.00%
Term of debt						4 years
Notice period for principal paydown of debt						6 months
Management Company
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of employees having ownership interest in the investment properties	6
Minimum \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Interest rate (as a percent)	3.76%
Minimum \| Limited Partnerships
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Percentage of ownership interest	40.00%
Minimum \| Harold Brown
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Percentage of ownership interest	43.20%
Maximum \| Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Interest rate (as a percent)	5.97%
Maximum \| Limited Partnerships
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Percentage of ownership interest	50.00%
Maximum \| Harold Brown
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Percentage of ownership interest	57.00%