Hello!
I've spent a lot of time in robigo, it's helped me buy basically every ship I want in the game plus about a billion bucks to play with afterwards. I've tried most of the obvious ship choices, large and medium, and can safely say that going with a medium sized ship from and only grabbing missions from Robigo Mines is the way to go.
You can fit more passengers in a large ship based at Hauser's reach, but remember these are VIP missions so the raw number of passengers doesn't matter- it's the number of missions you can complete on each run. You will also have to deal with a lot of illegal passengers which means silent running and heatsinking your way in every single time. You will not get scanned at Robigo mines however. For me this was a no brainer because I like to use Auto dock and just AFK or tab out and do something else while docking. But hey if you like supercruising twice as far and dealing with security scans then be my guest
The most passengers I've seen for any one of these robigo passenger missions is like 15 or 16 so fitting anything larger than a 5E passenger cabin is a waste of mass. There are a few high paying business class missions you will find assuming you have good rep with the mission giver so if you'd like you can bring along a business class cabin or two but I usually just stick with full economy cabins and wait for the mission board to refresh if I don't fill my cabins in one go. I've never had to wait for the board to refresh more than once before I'm loaded up and ready to go again.
Engineering isn't required but ideally if you can make it to the tourist beacon and back in 2 jumps you're pretty optimized (it can be done in 1 jump there and back in a krait phantom but you will sacrifice most of your passenger space for that kinda jump range and it just ain't worth it for 1 less jump imho)
Here's the build I use -
https://s.orbis.zone/e282
Python seems like the obvious choice here, and it is. But the engineering and downsized core interals allow it to do the run in 2 jumps there and back, without engineering its gunna be around 4 jumps there and back depending on your build.
I can consistently make over 100 million an hour with this build, usually more like 110-120 million. Assuming you've got full rep with all the mission givers you can expect up to 15 million per turn in, that's roughly 2.5 million per mission. There's ways to make more money sure but boy this is easy as hell haha.
Good luck!
o7
