Having doubts about having a haircut, advice?

Do not let them thin it. Your plan sounds good already without them thinning it with that "hair thinner." LOVE your think, beautiful hair. It you get it thinned with that razor thingy, your hair will just look like a bunch of split ends and hairs that looked like they were chopped off. This is coming from someone who has very thick, curly, and long hair.