All you really need, is some nicotine solution, some PG, some VG, a couple blunt tip measuring syringes, and a couple empty e-liquid bottles, which, you could buy, or, you can use your old/used empty liquid bottles. Other than that, you just need a DIY calculator, and your flavorings. I recommend you order some "crisp" flavoring, as it does make a lot of juices a lot tastier (tobaccos, fruits, keylime pie) you may want to get a couple 50ml empty bottles for mixing as-well, if you plan to mix in large amounts. Other than that, you're good to go! A starter kit is a great idea, just make sure you aren't getting ripped-off for the price of convenience!

you can get some great prices on nic solution by shopping around. MyFreedomSmokes has some good deals on pure nic, if you ask me. I've been out of the DIY game for a while now, though.. So, Idk the cheapest sites anymore. GL with your new DIY hobby, and enjoy your vapin' journey!