You May have the Question that how can I reach out your flippa auction to more buyers?
1.) Facebook: I will post your link of flippa auction to domain groups of 50. Each group has nearly 2k members, some may have 8k members. You will get more views by potential buyers. I can say approximately 100k members who are the potential buyers know that domain/website for sale.
2.) Linkedin, Professional compared to fb. you will find more higher authorities of the company including directors,chairman,CEO,President. Here we have 30 groups which is less compared to FB group but qualitative! It will have great exposure to your domain/website. More powerful!
3.) Twitter - Consider it as a extra gift, Since I am also a domainer, I have the follower of 2k who are the potential domain buyers, though I have more followers. I am only targeting the people who really going to buy domains/websites.
4.) Forums! - I am a active member of forums especially - Namepros ,DNforum! where these are the forums dedicated for domains/website selling and buying!
Hereby, I am assure you that your auction will be known to may of the potential domain/website buyers.Thanks.