A couple of ego batteries with passthroughs(come with charger cords so no need to buy a charger)
I'd recommend at least a 900mah rating on the battery for longevity and flexibility.
Some "knockoffs" come with variable volt capabilities, 3.2-3.7-4.2 which is nice for a little flexibility.
You can tailor the heat and TH a little for different juices and cartos/attys/tank configurations.
Around 45-50 bucks for 2 of these.
There are a great many options available for what to put on top of these.
I really like the new ego vision stardust clearos, you can see the liquid(just my preference). Get the LR version for more flavour, vapour and heat.
You may also like the standard resistance(SR) however.(longer batt. life)
They hold 1mil-1.3mil of juice so you would need a least 2 to get you through
the day without having to refill. That said they do perform better when they
aren't running low. These need to be rinsed out and dryburned after 3-6
refills or every 2 to 3 days depending on the juice you're using.
6 bucks each
Many like varying cartomizers, take your pick on type but I'd recommend an
XL, XXL or XXXL size, these perform best if they are always filled up
and kept wet. They have a filler material in them.
5 in a pack from 6-10 bucks.Should last you up to a few weeks (if you keep them wet after the first fill)YMMV
More disposable than the stardusts.
You'll need a couple drip tips(510 size) only if you go for
cartomizers, and some juice.
Not getting into attys and carts as from the info you've provided
they may not suit you. More refilling involved.
These are my recommendations only, the final choice of course is all yours.
Cheers

EDIT: got logged out while typing then dinner called, made a couple minor changes.
sorry for that!