$290,000 related to legal, accounting and other professional fees. For the three months ended March 31, 2022, approximately $128,000 related to stock-based compensation, $753,000 related to payroll and payroll related expenses, $301,000 related to other corporate expenses, including board fees, corporate office rent and insurance and $320,000 related to legal, accounting and other professional fees.
Pension related costs remained relatively flat at $144,000 for the three months ended March 31, 2023 compared to $158,000 for the three months ended March 31, 2022. These costs represent professional fees and other periodic pension costs incurred in connection with the legacy Syms Pension Plan (see Note 8 – Pension Plan to our consolidated financial statements for further information).
Cost of sales – residential condominium units increased by approximately $6.6 million to $12.3 million for the three months ended March 31, 2023 from $5.7 million for the three months ended March 31, 2022. We closed on five residential condominium units during the three months ended March 31, 2023 as compared to three residential condominium units during the three months ended March 31, 2022. Cost of sales consists of construction and capitalized operating costs that are allocated to the respective condominium units being sold, as well as closing costs of the residential condominium units. Units that we closed during 2022 were generally lower priced, smaller units on the building’s lower floors, many of which entered into contract during the height of the pandemic.
Depreciation and amortization remained flat at $1.0 million for the three months ended March 31, 2023 and 2022, respectively. For the three months ended March 31, 2023, depreciation and amortization expense consisted of depreciation for the Paramus, New Jersey property of approximately $282,000, depreciation for 237 11th of approximately $412,000, the amortization of lease commissions and acquired in-place leases of approximately $192,000 for 237 11th, and amortization of warrants for $114,000. For the three months ended March 31, 2022, depreciation and amortization expense consisted of depreciation for the Paramus, New Jersey property of approximately $283,000, depreciation for 237 11th of approximately $382,000, the amortization of lease commissions and acquired in-place leases of approximately $224,000 for 237 11th, and amortization of warrants of approximately $114,000.
Equity in net loss from unconsolidated joint ventures increased by approximately $750,000 to $4,000 for the three months ended March 31, 2023 from equity in net income of $746,000 for the three months ended March 31, 2022. Equity in net loss from unconsolidated joint ventures represented our 10% share in 250 North 10th, which was sold in February 2023, and our 50% share in The Berkley, which was sold in April 2022. For the three months ended March 31, 2023, our share of the net loss is primarily comprised of operating income before depreciation of $121,000 offset by depreciation and amortization of $77,000 and interest expense of $48,000 for 250 North 10th. For the three months ended March 31, 2022, our share of the net income is primarily comprised of operating income before depreciation of $436,000 offset by depreciation and amortization of $348,000, interest expense of $183,000 and the income from the change in the fair market value of the interest rate swap of $841,000.
Unrealized gain on warrants increased by approximately $435,000 to $66,000 for the three months ended March 31, 2023 from an unrealized loss of $369,000 for the three months ended March 31, 2022. This represents the change in the fair market valuation of the warrants due mainly to the change in our stock price on the measurement date.
Interest expense, net increased by approximately $3.5 million to $6.3 million for the three months ended March 31, 2023 from $2.8 million for the three months ended March 31, 2022. For the three months ended March 31, 2023, there was approximately $7.0 million of gross interest expense incurred, $689,000 of which was capitalized into residential condominium units for sale. For the three months ended March 31, 2022, there was approximately $4.3 million of gross interest expense incurred, $1.5 million of which was capitalized into residential condominium units for sale. The increase in gross interest expense was mainly due to higher overall interest rates on our loans after March 31, 2022.
Interest expense - amortization of deferred finance costs increased approximately $456,000 to $892,000 for the three months ended March 31, 2023 from $436,000 for the three months ended March 31, 2022. The increase was principally due to less capitalized amortization of finance costs for our loans as part of residential condominium units for sale.
We recorded a $124,000 tax expense for the three months ended March 31, 2023 compared to $70,000 for the three months ended March 31, 2022.
Net loss attributable to common stockholders increased by approximately $1.1 million to $6.2 million for the three months ended March 31, 2023 from $5.1 million for the three months ended March 31, 2022. This is a result of the changes