One of The Elder Scrolls V: Skyrim's seedier side quests is joining the Thieves Guild. Based in The Ratway below Riften, the guild is a faction focused on theft in all its forms. Though the game makes it seem there's only one method of entering the criminal organization, there is a lesser-known, alternate way to join Skyrim's Thieves Guild that doesn't involve sending the Dark Elf Brand-Shei to jail.
"A Chance Arrangement," the quest to join the guild, begins when the player speaks to Brynjolf, a member of the Thieves Guild residing in Riften. He tasks them with stealing a silver ring from Madesi, an Argonian jeweler with a stall in the Riften market. From there, while Brynjolf stages a distraction, the player must sneak behind Dunmer merchant Brand-Shei and plant the ring in his pocket. Success will automatically trigger one of Skyrim's guards to arrest and jail Brand-Shei, and Brynjolf will extend a guild membership to the player.
Despite the perks of Skyrim's Thieves Guild membership, jailing Brand-Shei can be a hinderance, as it removes the option to buy from and sell to Riften's only general merchant. However, as recently pointed out by TheGamer, not completing or failing "A Chance Arrangement" does not cut players off from the guild opportunity; rather, failure is another means to garner an invitation from Brynjolf.
Joining Skyrim's Thieves Guild: Alternate Method
One way players can fail Brynjolf's assignment is to get arrested, either by getting caught while stealing or planting the ring or by outright attacking someone in the area. Alternatively, players can simply go inside a building after Brynjolf begins his distraction, which will automatically end the quest. After the quest is failed, players should then go talk to Brynjolf. He will be quite disappointed in them and won't offer payment for the job, but he'll offer them the chance to join the Thieves Guild, nevertheless.
Following these steps will let players both join the guild - which leads to one of The Elder Scrolls V: Skyrim's stronger quest chains - and continue trading with every merchant in Riften. Because each merchant in the game has only a set amount of money at a time, having as many available as possible will alleviate a lot of potential frustration when players seek to offload their useless goods for coin. Along with the stolen items they gain, Thieves Guild members will pick up a decent amount of legitimate loot, so they may want to keep Brand-Shei out of jail.
Source: TheGamer