Well, his coaching profile states that his USCF rating is 20160. Seems legit.
Chess Coach Qualified?

I think 20160 is his ZIP code. Have you explored any of his games to see if his coaching is warranted?

The only thing you need to be on guard about is if his coaching strays to a topic that is clearly not in his wheelhouse based on his rating. If he's coaching about basic tactics and opening principles, fine (although there are more efficient methods of learning both of these than taking lessons from a coach, even a free one). But when he starts talking about things such as middlegame planning or complex endgame psotions, be wary as these are ares where the overwheliming majority of 1200s are lacking in understanding.
Edit: And yes, even some of the basic advice he gives may not be correct, or he may be misapplying it. There are plenty of resources on the internet that you can check his advice against. But if you're going to go through the trouble of doing that, you may as well just be learning on your own and the only reason to take him on as a coach is to give him a bit of coaching experience.

But how am I supposed to know what is within his "wheelhouse" and what is not, if I am a total beginner?

You can find out what he plans to teach you, and post it here. Someone will let you know. Like I said, if it's "opening principles" you're probably safe as most 1200s know these pretty well(though they don't always follow them). If his plan is to show you a bunch of grandmaster games and analyze them with you, I'd be wary. Things that fall in between this are a judgment call. If in doubt, ask.

Can he teach how to play an opening like this? This is a "on line" game where the start position was set, his first move was move 3.

Woah, black goofed big time in that game.
On a more serious note, I agree with BetweenTheWheels that you should try to teach yourself. For one thing, there are a lot of free chess material on Youtube that you can take advantage of. You shouldn't feel that you need a coach or anyone else holding your hand in order to make improvement, especially as a beginner.

Okay, I completely take back anything I said about there being the possibility you could learn something from him. Based on that game, he's not qualified to teach ANYBODY.
Actually I had a look at one of your games (the loss) and I'll give you some free advice based on that game. First, always make sure that when you make a move, you're not just leaving a piece or a pawn where it can be just taken (see your 1st move). Second, avoid early queen moves. Since the queen is the most powerful piece, you will have to move it every time it is threatened by a lesser piece, and they can use this gain of time to develop their pieces. Certainly don't make two or three queen moves before bringing out any other pieces. In your loss, you got to move 8 before you moved something other than a pawn or your queen.

I don't think people under 2000 FIDE could make good teachers/coaches for adult players.
Better to learn by yourself than with a guy rated 1200/1500 : he could only teach you his bad habits IMHO.

Do you really need a coach? Perhaps not, try here first..
http://www.chess.com/groups/forumview/101-essential-chess-tips

That guy's worst than me,and look at my rating. =P
That's not the main point.Main point is,he said his USCF rating is,well,10 times higher than the current highest rating.Not only that,he is too ignorant.USCF ratings are not in numbers,but in class (letters).Also,any decent chess player won't be arrogant and declare themselves as 'to be chess champ'.
I was looking at some posts and saw this profile of:
http://www.chess.com/members/view/thebest1992
who is offering chess coaching also at http://lionelchesscoaching.webs.com/
Since I was looking for a chess coach on-line I am interested but have you seen this guys credidentials?
If any experienced players want to check out the coach's "on line" games here and please tell me if this gentleman has the cred to coach? Appreciate.