It's a group giveaway where 20-30 authors pool their money to create a prize pack of amazing goodies, and then run ads and do promotion to get as many people to enter the giveaway as possible.

At the end of the giveaway, the email list is distributed to the authors. Contestants know they are signing up for all the mailing lists when they sign up, too. So you aren't buying a random list, you are getting a list full of people who know they will be getting emails from you.

Mailing list builders run for two weeks, and then emails are distributed once the winner claims their prize. The whole thing from beginning the giveaway to finish takes about 2 weeks.

Builders run once 20-30 people sign up for them. It's a great way to seed a new list or to add new potential buyers to your existing list.

Book sales are almost entirely influenced by the size of your audience. The more people who know your work, the more people buy your work. The more people buy your work, the more people love your work. The more people love your work, the more people tell other people about your work, and it becomes a virtuous cycle.

With the average cost of a book around $3.99, you need thousands of readers in order to build a successful career. It could take years to build that kind of readership, but mailing list builders short circuit that time frame and deliver thousands of potential fans to you quickly and affordably.

You have to do the work to engage them, and builders are no guarantee for success, but think about this for a moment. What would you do with thousands of potential fans delivered to you? How would that change your career?

The difference is how we acquire subscribers. In an ad based builder, we are acquiring subscribers through ads to completely new people who like certain fandoms.

These are people who are not on anybody's existing mailing list, and thus do not require any social sharing at all.

Sharing based builders are the opposite. They are built only through people sharing with their mailing list and on social media. All of the subscribers are built through the participant's mutual mailing list, and thus require two newsletter sends and daily social media sharing. You must already have a mailing list, even if it is only a couple of people, in order to join.

Ad based builders are great for people who already have an established list because they search for completely new people. Once you have a large list, the sharing based builders become less helpful for you because your already existing subs make up a large percentage of the overall list.

However, because ad based builders are completely new subscribers, they are less engaged them a sharing based builder at the beginning. You have to do a lot more to warm them up and get them excited about your work.

Unlike sharing based builders that lose effectiveness over time, ad based builders can be done forever, because there are always new subscribers to find in different fandoms.

Sharing based builders are great for people with smaller lists, or for people who want to get highly engaged subscribers.

All of the subscribers from a sharing based builder are already part of a mailing list, and they know how they work. They are also readers, so they have a higher tendency to engage with your email list.

Frankly, both are great, and I recommend you doing some of each, which is why I offer both types.

Results vary depending on the builder. Ad-based builders result in roughly 3,000-6,000 new subscribers, with the average around 5,000.

Sharing based builders result in 1,000-3,000 subscribers, with the average being 2,000. Since sharing based builders must be shared with your list, you will get more existing subscribers with a sharing based builder than an ad-based one.

After somebody signs up for the giveaway with their email, they are offered opportunities to get more entries by following people on social media (Facebook, Twitter, Youtube, Bookbub, etc.).

These are called social media boosters because they boost your social media accounts, getting you on average of 50-200 new people following you on social media with each builder, though results vary.

I'm not sure anybody can say anything is 100% GDPR compliant, but these are the steps I take to maintain compliance.