I'm not going to recommend a RTA to someone who is a non-smoker, doesn't know what that acronym is, and who has foggy ideas about anything, including whether they want to vape at all, once they try it with 0 nicotine. It's just a large investment of time/money skill building (which you need lots of) and whatnot. I'd buy a really cheap sub-ohm starter kit with a USB charger and internal battery (with adjustable wattage) for you to TRY vaping and see how you like it. You may hate it. You may decide you want a different hobby (for ppl who are into clouds, I always recommend taking up a wind instrument-- you'll be inhaling and exhaling sound, very satisfying, and you'll probably IMPROVE your lung capacity, not deacrease it). Disclaimer, there isn't really sound, proven data out there that says that vaping is harmful but not much indicating that it's BETTER for you than clean air (though... depending on where you live...) Buy a cheap kit, you can upgrade later. Seriously. Were I to take up a hobby, I woud not be running out and purchasing the most expensive, complicated thing I could find.... Only to abandon it 2 weeks down the line.
That said, I think Brother Bob has provided you with enough information to get started. Let me add, you will have the costs of creating or buying a build kit (not cheap, right there) wire, cotton, learning to wrap it, figuring out if your coils are even safe to drip/vape on, and a whole host of other issues. It's not a matter of buying extensive kits and then thinking you can rebuild with the $2 worth of materials that will arrive with the kit. You'll also need batteries, chargers, the list goes on.
That said, good luck with whatever you decide!
Anna