In case of a lump-sum or fixed contract, you do not show the line items on an invoice as they are simply ‘built-in’ to the overall fee. However, if you still want to attribute the cost of the fees to the project so that you get an accurate financial picture, it is recommended to assign these expenses to the project and have marked them as non-billable.
You must record the bills for projects as expenses and make sure that they are marked as non-billable. That will tell BQE CORE that these expenses are part of your fee or contract amount. The job/project costing reports will include them as cost to the job because you marked them as non-billable.