16. Related Party Transactions

During the three months ended March 31, 2026 and 2025 the Company engaged in transactions with Envision Homes ("Envision"), which is a related party due to common control under a Company equity holder. The Company recognized $6,546 and $9,535 of sublease income for the three months ended March 31, 2026, and 2025, respectively. There were no outstanding balances due from Envision as of March 31, 2026 and March 31, 2025, respectively. All transactions with Envision were conducted in the normal course of business and on terms equivalent to those that prevail in arm's length transactions.

During the three months ended March 31, 2026 and 2025, the Company engaged in transactions with Wellfield Development ("Wellfield"), which is a related party due to common control under a Company equity holder. The Company recognized no revenue for the three months ended March 31, 2026 and 2025. The outstanding balances due from Wellfield as of March 31, 2026 and March 31, 2025 are $- and $14,422, respectively, which are included on the accompanying condensed consolidated balance sheets as accounts receivable, net. All transactions with Wellfield were conducted in the normal course of business and on terms equivalent to those that prevail in arm's length transactions.

During the three months ended March 31, 2026 and 2025, the Company engaged in transactions with Park Towns ("Park"), which is a related party due to common control under a Company equity holder. The Company recognized revenue of $14,471 and $38,857 for the work performed for Park for the three months ended March 31, 2026 and 2025, respectively. The outstanding balances due from Park as of March 31, 2026 and 2025 are $- and $215,738, respectively, which are included on the accompanying condensed consolidated balance sheet as accounts receivable, net. All transactions with Park were conducted in the normal course of business and on terms equivalent to those that prevail in arm's length transactions.

During the three months ended March 31, 2026 the Company engaged in transactions with the previously consolidated VIE, CCCRE Holdings ("CCCRE"), which is a related party due to common control under a Company equity holder. The Company recognized $33,804 of lease expense for the three months ended March 31, 2026 related to a leased office warehouse and equipment yard which began in November 2025. We expect to pay CCCRE $144,000 per year under the lease through November 2030. Management believes the terms of the lease are consistent with market rates and comparable to those that could have been obtained from an unrelated third party. In addition, the Company entered into a separate lease agreement with CCCRE with an initial term beginning January 1, 2026 and extending through January 31, 2041 with annual base rent of approximately $1,140,000. The commencement of this lease is contingent upon the issuance of a certificate of occupancy, which had not been received as of March 31, 2026. Accordingly, the lease had not commenced as of March 31, 2026.

In September 2025, the Company entered into a new lease with King Road, LLC ("King Road"), which is a related party due to common control under a Company equity holder. The Company recognized lease expense of $60,000 for the three months ended March 31, 2026 related to leased land for purposes of operating an equipment yard. We expect to pay King Road $120,000 per year through December 2030. Management believes the terms of the lease are consistent with market rates and comparable to those that could have been obtained from an unrelated third party.

In February 2026, as part of the ALGC transaction, the Company entered into two separate 15-year lease agreements with an entity under common control with the seller to lease the existing operating and office facilities of ALGC. The Company recognized lease expense of $75,560 for the three months ended March 31, 2026. We expect to pay $600,000 per year through February 2041 with 3% annual increases.

In connection with the IPO, Cardinal Infrastructure Group Inc. utilized some of the net proceeds from the IPO to redeem 7,500,000 OpCo units for $157,500,000 from the group of Continuing Equity Holders, which includes Erik West, the Chief Operating Officer of Cardinal NC, Mike Rowe, our Chief Financial Officer, and Jeremy Spivey, our Chief Executive Officer. Additionally we entered into a Tax Receivable Agreement (“TRA”) with the Continuing Equity Holders. The TRA provides for payments by the Company to the Continuing Equity Holders equal to 85% of certain tax benefits that the Company realizes, or is deemed to realize, as a result of increases in tax basis arising from exchanges of LLC units for Class A Common Stock (or cash) and from certain other tax benefits related to payments made under the TRA. The Company retains the benefit of the remaining 15% of such tax benefits. The TRA liability is recognized when the related tax benefits are realized upon exchanges of LLC units. As of March 31, 2026, the tax receivable agreement liability on the condensed consolidated balance sheet totaled $39,423,529 . Refer to Note 13. Income Taxes and Tax Receivable Agreement for further details.