Firstly, the contract price should be determined according to the reasons for the change of visa. The reasons for the change of visa include those proposed by the contracting party, those proposed by the construction party, and those caused by the errors in design and exploration that make it necessary to modify the drawings, as well as changes due to other engineering environment changes or new technology requirements. Auditors need to carefully analyze the reasons and reasonably determine the contract price. For example, the engineering claim costs caused by inaccurate geotechnical investigation reports leading to design changes should be borne by the geotechnical investigation department; if the increased costs are caused by unreasonable construction, the construction party should bear the responsibility. Auditors should note that not all additional costs resulting from changes in visas are the responsibility of the construction unit. The principle of "whoever makes the change is responsible" should be followed.
Secondly, the contract price should be determined according to the content of the change visa. Auditors must be able to read and understand the drawings thoroughly. They need to ensure that the content of the change visa is true, not duplicated, the calculation of the quantity of work is accurate, and the procedures are complete. The signatures and seals of both parties (Party A and Party B), the design unit, and the supervisory unit are all essential. In addition, the actual site measurement should be combined with verification. By comparing the changed dimensions with the original drawing and the actual situation repeatedly, the truth can be easily seen. Have the reduced projects been visaed? The purpose of doing this is to prevent the construction unit from increasing the cost by only making additions without reductions.