You may NOT request/promise a vouch or request a free service

This means posting on your thread "giving vouch out if you train my account", or anything similar to that matter. This will break down on scammers getting unneeded "trust" for no reason.

Vouches should only be given out if the person has done a good service to you. Someone doing the training should not ask for a vouch, but wait for it to be given if it is deserved.

You may offer free services but you may not request them as it is considered as begging.