legal ground
Article 470 of the Civil Code
The contents of a contract shall be agreed upon by the parties, and generally include the following clauses:
(1) The name and domicile of the party concerned;
(2) Subject matter;
(3) quantity;
(4) quality;
(5) Price or remuneration;
(6) Time limit, place and method of performance;
(7) Liability for breach of contract;
(8) Methods for resolving disputes.
The parties may conclude a contract by referring to the model texts of various contracts.