1. Protank 2 (NOT 3, the dual coil heads suck). I know its not really seen as an RBA, but the Protank coil heads really shine when you rebuild them yourself. Comes with 2 coil heads in the package, and that should be all you ever need. For rebuilding, all you need is Kanthal, organic cotton, and a torch of course. I really do believe that a well built Protank head with cotton can produce rich, flavorful, and dense vapor comparable to high end RBA's.
Another plus for beginners is that if you start with a Protank, you can learn and get comfortable with wrapping coils and wicking before you step up to more complicated builds. With every tank that uses Protank heads, you can remove the coil head WITHOUT draining the tank, and potentially losing/wasting e liquid and time getting your atty up and running again. With Kayfuns, Oddy's/Ithaca's, and other high end rebuildable tanks you pretty much have to drain it if you want to rebuild it while there's still juice in the tank. Trust me, you'll be rebuilding a lot when you start out, and even once you master it (because its fun!!!

).
$15, you can't go wrong, a great start.
2. A good Kayfun or Kayfun Lite Clone. I'd stay away from fasttech Kayfun clones, and go with an EHpro or Hcigar clone. $30-$50, That's bang for your buck.
3. If I won the lottery? It wouldn't be just 1 atty, lol. GG Ithaca, Authentic Kayfun, Arrow 22, Arrow 17, and tons of drippers. By the time you get to stage 3 you'll have a good idea about what you do and don't like. This is why I suggest starting at 1.
An example of buyers remorse is the Terminator C I bought last month. Resistance wire and no resistance wire is just not for me. Far too involved of a build for not that amazing of results. To me, that's money wasted, but its all part of the learning process.
I love my Kayfun clone, I can probably build it in under a minute, and the vapor is satisfying to say the least.
Sorry for the long winded response. I just like to share my experiences in the hopes of helping my fellow vapers.
Vape on!
**Stay away from gennies until you are really comfortable building, or you risk reverting to analogs

***
Edit: +1 for igo's. I have an Igo-W I rebuild probably everyday because I'm mental I guess.