Welcome to the 3rd generation of vaping (it's moved on a little since then).
Coils should last you, well, it depends - there's a bunch of variables in play... Generally speaking the biggest two are the wattage you're vaping at (power equates to temperature) and the flavourings in the liquid.
I'm a little confused as to what kind of mod (battery kit) is being used... I find references that it's regulated at a fixed 4.2V which, with a 0.27 ohm resistance in the coil indicates should mean that you're vaping at 65 watts, yet the coil seems to have 40 to 55 watts printed on it. Thus I can't comment on that variable.
Regarding juice (eliquid), some flavourings (deserts especially) are more prone to clogging up the coils and thus corrupting the cotton. You'll know when this is happening because the flavour will diminish in quality (eventually becoming hot / horrid and not terribly good for you - although you'll not vape that because it is so very very unpleasant).
The obvious last variable is how much liquid you vape... Now, that's an interesting one - you've ventured into the world of `sub-ohming` / direct to lung inhales - you will get through juice much faster than you would at lower temperatures. Bottom line is that there isn't an answer to your `how long` question.
I vape using the old school tech (unregulated mods.. as charge decreases the voltage drops) and typically vape (mouth to lung) at between 15 to 19 watts. I use Kayfun's and build my own coils using Kanthal wire and Ken Do Gen cotton (clean, organic and excellent wicking properties). Recoiling takes me about ten minutes and I'll change coils every 3 to 7 days, depending upon what I'm vaping and how much. Typically I vape around 40ml a week at 12mg/ml
Liquid - it's rare for me to buy pre-made liquid as I mix my own. I do this partly for cost (I am not what some would call well-off), partly because I know exactly what I'm using and how the organic flavours break down under heat and partly because of the compensation scheme for tobacco and pharmaceutical companies for this disruptive technology (Article 20 and the European Tobacco Products Directive) requires a certain amount of future proofing before a black market becomes a necessary evil. It's odd how concious I am about safety given the length of time I used a nicotine / CO mix infused within tar and various nasties like formaldehyde and heavy metals.
My path is all a bit complicated for a newcomer like you.
I've not heard bad things about the one pound e-liquid folks but for links, recommendations and general information, I suggest you lurk around the very friendly
AAEC forum (mods, please remove the link if not permitted). You'll find me under the same alias although I'm not terribly active these days. You'll find discount codes and, hey, perhaps introduce yourself. Be warned, though - exposure to the denizens of that particular room is even more expensive than here.
Good luck with both abstinence and fatherhood (they are both great).