As a personal rule of thumb, only one out of 20 people answers to any query. IMO you simply need to send emails/fliers/etc to 20 times the number of sellers yo

As a personal rule of thumb, only one out of 20 people answers to any query. IMO you simply need to send emails/fliers/etc to 20 times the number of sellers you aim at recruiting. For the email content: It should be very short (less than 500 words) and mostly explain why it is interesting for a seller to use your platform. Good luck!