Custom servers are on the way for Sea of Thieves. These servers will allow you and those you choose to join to experience game content without having to worry about being attacked by a random group and you won't have to worry about losing your hard-earned loot when you were t paying attention. The ability to have a custom server is not readily available. It will first release as an early alpha to a select number of those in the Sea of Thieves Insider Program. The exact date of this alpha test remains unknown, and there is no specific date for when it will be available to everyone who owns Sea of Thieves.
A custom server will allow you to create unique adventures, determine custom ship numbers and what types they can be, and share the server code with those you want to join who can play with other people. Unfortunately, any gold or reputation progress you make on the custom server will not make its way to the live Sea of Thieves game or to your account.
If you want to run a custom server, it will cost you a lot to run and maintain. The exact price of the Sea of Thieves custom server remains unclear, but those details will become more available once developer Rare has more information to share. At the time of announcement, custom servers have a lot of bare features that they want to develop and populate before sharing them with the public. We can expect to hear more as alpha testers play around with it and provide feedback to developers.