Facts:

The defunct Petroleum Trust Fund (PTF) awarded a contract for the building of a dam at Sabke Village, Daura Local Government Area of Katsina State to the appellant. The appellant in turn subcontracted to the respondent for the building of eleven residential quarters where the appellant’s Senior Engineers would reside. The respondent was given a design made by a company for the building of the residential quarters. However, before the construction of the residential quarters commenced, the appellant gave the respondent another design made by another company. The specifications contained in the two building plans were different as one contained a useable area of 173 metres, while the other had a useable area of 110 metres. There were also differences relating to roofing, tiling, ceiling, doors, etc. It was stated in the subcontract that the respondent would be paid 60% of the amount paid to the appellant by PTF. The appellant paid the respondent in instalments as the construction work progressed. After the completion of the project, the parties were at an impasse regarding the exact amount due to the respondent and how much was left, if any, to be paid to him. The respondent wrote to the appellant demanding his balance, but he was paid the sum of ₦2,526,000.00, such that the total amount paid to him prior to the commencement of the suit was ₦22,026,869.02. Due to the inability of the parties to reach a conclusive agreement on the amount to be paid to the respondent by the appellant, the respondent instituted an action before the trial court via a writ of summons and statement of claim and sought certain reliefs.
At the conclusion of the trial, the trial court in its judgment found that the parties had abandoned their agreement under exhibit 2 and that the respondent expended his personal money on the project and he would ordinarily be entitled to claim on quantum meruit basis. However, it held that the amount claimed was not proven and it dismissed the claim.
Aggrieved by the judgment of the trial court, the respondent appealed to the Court of Appeal. The Court of Appeal allowed the appeal, set aside the judgment of the trial court and ordered that the appellant pay to the respondent the sum of ₦7,622,9SS.98 as the reasonable sum on quantum meruit basis, having earlier paid him ₦22,026,860.02 and the sum of ₦500,000.00 as general damages.
Dissatisfied with the judgment of the Court of Appeal, the appellant appealed to the Supreme Court.