I have never heard of this. It sounds like he just made it up. Either he or the subs should be fixing damage they did. Is there anything in your contract about damage?

Nothing about damages in the contract. GC agreed to pay for damages, but is now tacking on all these coordinating contractor fees. I haven't been a difficult client or delayed things etc, that's not his reasoning. By GC's own words, this fee is for his effort in picking up materials, overseeing subs, times spent driving to my place, talking to my KDs with questions he had etc. BAU stuff. I thought that this sort of thing is already rolled into his profit and general condition line item in the contract.

There is a clause in the contract saying any change in cost needs to be communicated in writing in advance, prior to work beginning. I plan to use that if costs get out of hand, but wanted to know if this sort of "coordination" fee is just part of the business.

He did some light work, which is his choice, I guess, instead of hiring a sub. But most of the work was done by subs.

Is this a Fixed Fee contract, or a Cost Plus? Things are handled differently if he is presenting you with a Change Order vs an accounting for the basis of the Plus on the Cost Plus.

That type of service absolutely is not a basis for a change order. It is part of his overhead in a fixed fee contract. It is not extra. If it is his Plus portion of the 25% markup on top of subs and materials in a cost plus, then he is wording it poorly.

Go back and read your original contract.

This is nuts. You shouldn't be paying any extra.