I think up until this point, Killer Merch was his bread and butter. They do everything, from sourcing the products, the printing, art direction, web site construction and distribution. That's fucking money right there.
However, all those warehouses he has been purchasing and the overhead to stock and staff them must be fucking insane. Shelving units, forklifts, work tables; keeping the lights on and the place climate controlled, insurance, salaries etc. It's astronomical.
Remember, when the James Charles debacle happened he was with Killer Merch. Jeffree shut James's online store and was about to start swinging. Jeffree would not have won that lawsuit, and he could have lost it all. That's when he decided he had to grow the fuck up, or his drama whoring was going to bankrupt him. Now he's set.
I think after this release, he could never work another day and live in the manner to which he is accustomed for 100 years, whereas, I think previously, that was not the case.
eta: Sorry, I didn't know I had this much J sperging in me, lol, but, did you notice how very delicately they danced around the JC drama? It was just Shane crying and jizzing and OH MY GAWDing that Tati said "fuck" and Jeffree saying something very neutral and non-incriminating. When, bitch, we know what happened and how it all went down.