You can get a Pico (no Melo tank) for $25 at Element Vape (good vendor)
Eleaf iStick Pico 75W TC Box Mod - JayBo Designs
Samsung 25R (excellent, recommended by among several other batteries by battery expert Mooch) for $5 from IMR (excellent battery vendor)
Samsung 25R 18650 2500mAh 20A Flat Top Battery
Charge by USB for now, add a decent $10 Nitecore charger down the road.
Aspire Nautilus 2 $19.99 VapeNW
Aspire Nautilus 2 $19.99
That's all just from a quick bounce around. If you don't mind waiting a bit on delvery you can use Fattech/Heavensgifts/3Vape for Chinese sites that will be a bit cheaper but only if you're patient on waiting for delivery. HOWEVER, don't order batteries from overseas (real customs headaches on Li batteries by international mail) or from places like eBay, you're far more likely to get a counterfeit that's more expensive than an authentic). There is a battery section on here if you want to review that, and I'll put up a list of recommended batteries, but really, any of the 18650s will be fine for you (although you don't need anything over 20A so no sense getting higher and having less runtime).
Then next month an extra battery, a charger, and your ongoing expense will be coils and juice. I've used evape.us for Nauti coils, ship from FL and they're reliable and $8.95 for a 5 pack.
Electronic Cigarette - Best Electronic Cigarette - Vapor Cigarette Aspire Nautilus BVC Coils (Pack of 5) at www.evape.us
Oh, battery list for the future if you want to get all technical
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