buying coils is such a waste of money. get urself a RTA /RDTA/ RDA and learn how to wick it urself with cotton.
most places will build you a coil for $5 which lasts for months and then you can learn to just wick it yourself(changing the cotton) or get them to do it for you
I recommend the geekvape ammit dual
https://www.geekvape.com/project/ammit-dual-coil-rta/