Knocking on Walmart candles? haha I use them when I need one. Birthday candles especially. Walmart sells them in twelve packs of solid colors, even special pink and black ones, so it makes my job much easier. Check around the birthday supply stuff. Also buy most of my herbs when needed from there because 9/10 times no one blinks or puts two and two together which I like. Don't need nosy people to start asking questions. I don't recommend dollar store candles though because the wick tends to remain and causes problems with the burn if you're using it for divination. But if you're not, then they should be good too. Just consecrate and use.
As for ingredients, that really depends. I've worked some with none and some with a bunch and both styles have worked. Depends on your mindset. When in doubt, meditate for a moment and you'll get an answer about what to do. I've already had everything ready to do one and when I was pre-meditating, I felt like most of it was unnecessary. Did it as I was instructed and it worked out fine. Also depends what kind of work you are doing. Rootwork for example I'd never attempt without having everything required.