This page in our guide to Days Gone contains the most important information about Hot Springs. You visit this camp early in the game and you will go back here regularly through the entire game.
Hot Springs Encampment is located in Belknap region. You will visit it early in the game. This happens during Price On Your Head story mission during which Deacon decides to meet up with Tucker and Alkali.
When you visit this place for the first time, the game will trigger a cut-scene. After that, Deacon will meet with Alkali and Tucker, the camp's leader. The next thing you will do is to drive with Tucker in a golf cart. After that, you will be able to enter and leave the encampment whenever you want.
Tucker can give Deacon various side quests (8 in total). Deacon receives a message through the radio every time a new side quest is available.
The mechanic in Hot Springs doesn't sell any bike parts (this isn't a bug). If you need to upgrade the bike, visit Copeland's Camp (later, you will be able to that in Iron Mike's Camp).
Alkali, the merchant in Hot Springs, sells new weapons. Don't buy a new primary weapon right away. Instead, you should wait until you reach Trust level 2 for Hot Springs and unlock new weapons. M40 sniper rifle, a special weapon, is available after reaching Trust level 1. This weapon is useful in eliminating single targets without alarming other hostiles (Alkali also sells suppressors). Once you reach Trust level 3, you can purchase SMP9. This weapon is much better than the majority of the pistols.