Which of the following is NOT a main type of construction contract?

Payment-in-advance contracts are not considered a main type of construction contract. The primary types of construction contracts typically include fixed-price, cost-plus, and time and materials contracts.

Fixed-price contracts involve a set price for the entire project, which provides financial certainty for both parties. Cost-plus contracts allow for reimbursement of project costs plus an agreed-upon fee, providing flexibility in accommodating changes and unforeseen circumstances. Time and materials contracts involve billing based on the actual time spent on the project and the materials used, allowing for adaptability during construction.

In contrast, payment-in-advance contracts are less common in construction and are not classified alongside the main contract types due to their specific application and limitations. They typically do not cover the same scope of responsibilities and outcomes as the established main contract types.