Maybe this is common knowledge, but I have not seen anyone do this.
There is a way to get to an off map Bandit Dook Hut that contains level 24 to 26 loot while you are at a low level. You can farm it and sell the loot to buy stuff that will be available in the next mission. Map Genie labels it a “Porta Potty”, but they note that it cannot be accessed until later in the game. This gives you early access to it.
Also, there is a White Chest that is not on Map Genie’s Borderlands 3 Interactive Map.
Off map Bandit Dook Hut and White Chest by docked Sanctuary
The Bandit Dook Hut has level 24 to 26 loot that you can sell before taking off in Sanctuary.
Run and jump from the top of the ramp next to the sphere.
The platform on top of the sphere has an invisible spot where you can jump on it.
The invisible area is just left of center as you look at the platform on top of the sphere.
Then a couple more jump/mantle’s and you can drop down to where the juicy loot is.
Map Genie has the location of the “Porta Potty”, but it notes that it is not available until after Sanctuary takes flight. This jump lets you get to it before Sanctuary launches.
The White Chest is on some elevated off map terrain. It can be seen from the Catch A Ride
beside Sanctuary and is a short climb and run.