Extract from the GTC - point 15 "Payment"
If no separate agreement exists, the invoice amount including VAT shall be payable promptly without deduction. Conceded cash discounts are not permitted if older invoices are still outstanding whose due date has already passed. Payments by bill of exchange are only permitted if they have been agreed with us. Payments shall be credited against the oldest outstanding claim in the following order: costs, interest, principal. We reserve the right to recalculate in the event of an error. In the event of default, the customer undertakes to pay default interest in the amount of 10% p.a.. All reminder and collection charges as well as the costs of legal intervention shall be reimbursed. In the case of custom-made products, a down payment of approx. 50% of the invoice amount for the ordered goods and for the costs incurred for temporary templates and designs is required. This amount plus VAT is due immediately after the order has been placed. Any bank charges incurred when transferring the invoice amount shall be borne by the buyer. Offsetting, retention or reduction against claims of the supplier is only permitted with counterclaims that have been legally established or expressly recognized in writing. Point 14 sentence 6, sentence 7 and last sentence shall not apply to consumer transactions.