few years back when I moved out of WH space I used four accounts to make T2 Hulls, I sat and mined while clicking industries and buy orders out of Jita 2 jumps away, while I sold all the hulls in Dodi for 20-30% jita sell markup. 12 characters building and inventing 120 slots.
TBH i did this when my plant shut down so no work for a few months meant lots of time lol and put 25 bill in profit into my wallet while still plexing 12 training toons. plex was about 620-800 back then.
the T2 market broke a while back when goons flooded the market, so I moved to NS for a while and learned how to run POS fuel, then with a new job I turned less time in game into a 50bill POS fuel per month, but profits were less .
its all how you play. Now I do PI and back 7 bill doing nothing but making P2s and Im happy with that.
you just have to find your niche