I used 5 1/2 packs of 100% kanekelon hair. At my local hair store they were about $2 a bag which isn't much at all. I cut off about 5-6 inches of the hair because it was a little too long but it still came down to just above my belly button which is fine for me. The only products I used while installing the twists were Palmer's Coconut Oil Formula Replenishing Hair Milk for moisture and a very small amount of Eco Styler Gel to help hold the twist and smooth my natural hair. I tried but wasn't able to twist from the root so I had to start each twist with a braid.
Overall, I really like how they came out and I'm gonna try to leave them in for at least a month. One issue I have is that I got the wrong color hair. The lighting in the hair store was more dim compared to the light in my bathroom so the hair was lighter than I thought but whatever. Also, I had trouble with a few of the ends unraveling. Sealing them with boiling water has worked for most of my head but a couple of twists keep coming loose. I may have to actually burn the ends although that's the last thing I wanna do. Either way, I'll definitely do this style again.
Here's a couple of pictures of the results:
I think I'd prefer them to be smaller but I'm not sure if I'd have the patience to do them myself.