I think what people buy depends on the amount of research they do, and their technical background. If they aren't afraid of the effort, they might just throw down for just about anything.
I've only been vaping since Sept 7th, 2015, so I do not know her gear at all. I could Google it but my point is just that everyone is different. By January, I'll have made my first batch of e-liquid, and I'm gunning for some intricate coil builds based off of what I can learn on YouTube.
Since I started vaping I've bought more than 2,500ml of e-liquids. Also picked up 5 Aspire tanks and an assortment of replacement parts for the tanks, a Mako Shorty RDA, kanthal wire, pliers, cotton, a 75W and 150W Sigelei box mod, 2 different battery chargers, 12 batteries, and a lockable carrying case for travel. I'd be building my own coils, but I need to pick up a small set of screw drivers....then all hell is going to break loose!
BS MIS, Iowa State University, AAS Cisco Internetworking.