It is more natural for this type of agreement to be drafted with care. Supplementary agreements are anything but a quick solution to certain business problems or requirements. They must be carefully considered, considered and formulated if they are not to be the cause of more problems than they solve. In a sense, nothing is worse than a dispute over a settlement agreement or an addendum, because the parties naturally tried to come to an agreement and settle things and did not want to spend money and management time to resolve the issues. Beware of correspondence or agreement on the back of a package that does not regulate or resolve anything. The fourth question is whether there is no prohibition on amending the existing agreement by a parallel agreement. An example is the type of contractual clauses that aim to exclude other documents from legal effect.