Arabella's Venture is a small merchant class vessel and is not far away from being too big for Bran. But he's really good with technology and has as much of it as possible fully automated. It's also something he's constantly trying to improve, as well. Much of the space has been utilized for different purposes.
Ship Systems and Command
Engine room, bridge. He can run the whole ship from wherever he is with access codes/voice command. He has a hydroponics bay to keep good oxygen on the ship, but doesn't do much with plants himself—it's all automated with plants that require as little care as possible. Everything he eats on board is usually from a replicator, and his system is fully recycling. The interior of the ship is mostly what you'd expect with industrial colors, but his quarters are green and brown.
Very spacious personal quarters, and quarters for crew/guests. His rooms are lived in, but not dirty or overly messy.
The main part is cargo space. Bay 1 is largest and used to house his wares—usually large lots of things he then sells or trades to others privately. Bay 2 stores technology he's picked up along the way—devices, components, replacement parts, etc., and his lab. Bay 3, the smallest, contains whatever it is that the ship's engines/power/holodeck run on.
The holodeck has quite a variety of programs he's picked up along the way, including a race car program, and several holiday planets and holonovel stories. However, he doesn't make overuse of it due to the power it takes to run it, and it's the first thing that gets turned off when he foresees needing to save power.