valuation - supply includes

Akshit Mittal (1 Points)

19 June 2019  
[b] any amount that the supplier is liable to pay in relation to such supply but which has been incurred by the recipient of the supply and not included in the price actually paid or payable for the goods or services or both;

please explain this provision, with example, whether supplier will reimburse for those expenses or buyer have to short pay for expenses incurred by buyer.