You lost me: Unaccrued staff costs are quite different than unrecognized revenue, which is what you originally mentioned. In fact, such costs would be on the liability side, so a sensible buyer would love to see you put them on the balance sheet since it would lower the assets in the company. (Buyers are always trying to accrue costs in advance, sellers are trying to accrue revenue in advance.)

I'm obviously not getting what you're saying.

As you said, a sensible buyer would love to see those costs on the balance sheet since it would lower assets in the company. Which is exactly what happened, and the buyer spent $150K less. However the OP was the seller, and so was significantly less delighted to find at the last minute that $150K less money than expected would be received.