Special construction scheme cannot be used as the basis for settlement, but written evidence such as supplementary agreement, meeting minutes, project contact list, project change list, project visa and other letters and records formed by both parties during construction can be used as the basis for engineering quantity calculation and determination of project price.
For the expert argumentation fee, it is generally the principle that whoever asks for it pays. If it is a construction plan, it will be paid by the construction unit. If it is a design scheme, it will be paid by the design unit.