Minimum Rating Requirement for a Chess Coach?

Rating obviously helps, but having the ability to explain things clearly and precisely will really make a difference.

Also young kids, they tend not to know much about chess. They win by getting complicated positions and calculating a lot. In quite positions sometimes you see them make really absurd moves that reveal how little they actually understand.

Some have studied, sure, but having an intuition about piece activity and pattern recognition isn't something anyone can verbalize, much less a kid who will be bad at teaching for the additional reasons you gave.

If people will pay for it, then it can't be a bad price

I sometimes visit clubs. Recently I saw an 1100 play a beginner. The beginner moved his queen a lot in the opening and had a bad position. The 1100 politely told them about the opening principles. Is that something worth paying for? Probably not, but it was valuable advice in the sense that it will improve that beginner's results.

The 400 point gap doesn't necessarily work at low ratings. In fact it can work in reverse at higher ratings. 2400 vs 2800, the 2400 can research things and give the 2800 info... but 600 vs 1000 does the 1000 actually know more things? After a few lessons the knowledge gap would be filled. 600 -> 1000 is mostly performance. People getting used to how the pieces move and not losing material, that sort of thing.

Some of my best lessons I have received have actually been from teachers only 200 points higher than I am on this site. But from what I've seen on this site, the difference in skill between a 1500 and a 1700 is not so large as the difference in skill between a 1900 and a 2100. I think a 2400 could teach plenty to a 2200, but I don't think a 1700 could necessarily teach a lot to a 1500. However, "sparring partners" are always good as well! Seems to be an upside-down triangle shaped progression toward point disparity's indicating greater skill. But for me personally as a coach, I like to have at least around 400 points between my rapid rating and theirs. I really want to feel that I have plenty to teach them. And in my personal experience it has worked very well for students who put in the effort. But yeah, high rating does not equal good coaching. I have had some phenomenal untitled coaches. I have had some horrible titled coaches.

Many coaches coach/teach very young players. They don't even know anything about it so id say a 1300 is qualified depending on the amount they are charging. As long as they are forthright about their elo etc before they start getting paid id say it's up to the parents of the kids getting coached. Basically the same thing as a baby sitter and you don't need any degree or experience in most cases to do that. 

Also just as an fyi as the op didn't seem to realize this there are at minimum 5 different types of chess teachers. The main ones being chess teacher, chess consulting, online chess teacher, online chess instructor, and chess instructor. All of which can have no elo requirement or low requirements depending on which of the 5 you are. The pay ranges from $28-$40 an hr at least in my state but there are states like NY you can charge $100+ per hr even just being 1300-1500 elo. I find it offensive op was basically making some people out to be scammers when this is very common practice. 

at least 100 uscf

A chess coach should hold some title, like a math teacher should hold a university diploma.
The ability to explain things clearly and precisely depends on a thorough understanding.

I'm in the former category, having peaked in rating terms a good many years ago at around ECF 160 (the old UK rating system - I think 160 is about 1850). Next to James, I'm clearly weak (and certainly weaker than I was at my peak) but I think I know enough and have enough experience to teach kids now. I do this on a weekly basis at our local library where I get great support from the staff there. I enjoy this and I've been told I'm good at it. And I should add that I don't charge. I do it because I love it. Some of the kids show some real promise but we don't have any prodigies with aspirations to titles, and I can still beat them all ... so far!

I have a good friend who runs a chess club who is rated in the 1800s, peak rating in the 1900s USCF. He has a large and successful following coaching young kids in chess, and many of his students have eventually surpassed him. So an 1800 can successfully coach beginner and intermediate players. I don't know if I would go much lower than that for paid services, but any chess player can give advice to someone who is weaker.

I did briefly play for the London U-12 team and the Middlesex U-14 team as a youngster myself before they found out I wasn't really good enough, I suspect. I also used to play in the London Junior Chess Championship played in a school in Packington Street in the Canonbury/Hoxton area then.

I don't think I have much say in this considering I am 1300. (I mainly play on lichess) I think that someone who is 1300 USCF could definitely assist a beginner who needs to learn different opening principles, middlegame ideas, and basic checkmates. However, when the apparent "beginner" begins to rise into the intermediate level, I do think that someone who is 1800-2200+ should take over. As they have better insight into how chess actually works, they also most likely have experience with the struggles of the stage the beginner is going through. (I am also still a child so I again say take this with a grain of salt)

The primary skills of a chess coach are centered around his or her ability to break a complex subject down into bite-sized logical pieces and then communicate them effectively to the student.

Actual chess skill is secondary. It's important, of course, but not as important as the two first-mentioned skills.

I've just been getting into OTB play recently, I'm projected at around 1800 USCF, and I personally feel that, assuming you are talking about a serious coach who is doing more than just teaching the basics, you should be a minimum of 2000 USCF. Even at 1800 USCF I know I have major weaknesses in my play(mainly in endgames) that I would have to patch before I felt comfortable coaching other players at a relatively high level.

Over 69 I think

Do you get students #38?

I'd say 2000 Fide, preferably with a title.

The problem with lower-rated coaches is that they will teach bad habits that players have to unlearn once they become better than said coach.

Coaches have to be able to teach high-level concepts. The problem is not that low-rated players can't see / understand GM-level type play, they can see it if they put in the effort. The problem is they get distracted and won't do it. This is where a chess coach comes in. If a chess coach cannot see all the way (all the lines and variations), he/she is not teaching chess.

I couldn't stop laughing when I read this post.

I believe if you are teaching the fundamentals of chess and general ideas to someone who has never played before I don't have anything against it. I could defiantly teach some principles but yes $30 is a lot for someone of that standard. Especially the amount of free courses and content on YouTube. I never spent a penny to get to 1200!