The appropriate translation for the "product price" clause in the contract would be:
"The current contract product price is established based on the product specifications and standards as described in this agreement. Any additional costs incurred shall be the responsibility of the respective party or subject to mutual agreement between both parties. If any changes in costs arise due to the respective party's reasons, the respective party shall assume responsibility."
The product price in this contract is settled based on the product specification standard indicated hereof in this agreement.
In case there is any additional cost,it should be borne by the buyer or negotiated between the two parties.
If there is a change of cost caused by the buyer, the buyer should pay for it.