A construction invoice is defined as a document in writing which reflects a business contract related to the developmental project or a building. These invoices specify the materials used for construction and the cost of labor used in the completion of the construction. They provide a breakdown of all the materials inculcated for the process of construction. These invoices are proof of your construction services rendered for the completion of a particular project. Payment is normally made at the end of the project completion and if any advance payment has been done before, it is to be mentioned therein.