The final account is due and I'm building my position

The final account is where every loose end of the project lands at once: the variations never agreed, the delay never compensated, the retention still held, the contra-charges threatened in passing. Most accounts are assembled in a hurry from whatever the job left behind, submitted high as an opening position, then eroded meeting by meeting because half the heads cannot survive scrutiny.

The stronger approach is the opposite: know before you submit which heads are proven, which need work, and which are time-barred or unpriceable, and submit an account built to be defended rather than discounted. The side with the better prepared file keeps the difference, and preparation is the one variable still fully in your control.