Yes, that is normal. What do I do? I do my COA's myself and save all the money and hassle. I don't replace the pads, but when the Straubingers do need to be replaced on my Powell I am probably looking at about $1000. Crazy, huh!
Usually you have to pay more to get the good service that the flute deserves.

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When I do need any pads replaced I most likely will send it to Tonya who works at the Miyazawa CO. She is amazing and does great work and I only trust her. Her prices are a lot less steap too. I had her do a ful overhaul on a Miyazawa flute for me, but she did mention that she used to work for Powell and does also do Powell flutes which I great for me.

$300 dollars is not unusual for a COA. Prices vary widely depending on area, tech, and in some instances, the level of instrument in question, but $300 certainly is not exorbitant for a top tier tech. I pay $350 for COAs on my instruments. My opinion is that after spending thousands of dollars on an instrument, it makes no sense to let it break down by cutting corners on maintainance. That doesn't mean you necessarily have to go with the highest priced COA you can find, but you need to find a tech who comes highly recommended by well respected performers in your area. I'm extremely picky with my instruments (but I play very expensive flutes/piccs), and I don't entrust them to just anyone...Some of the jerry-rigging I've seen done to instruments by supposed repair techs, and my knowledge of the shortcuts some of the lesser techs use makes me wary of most new techs. In fact, I regularly ship my flute across 3 states to have it repaired by someone whom I trust entirely. I assure you that this is not just a marketing gimmick...Maintainance and repair work is expensive, because when it's done right, it's extremely exacting work. Unduly cheap COA's usually cause additional problems that wouldn't have occurred had the work been done properly.

My tech is Paul Rabinov, and he does excellent work, which I would highly recommend. If you're interested, send me a message, and I'll be glad to give you his contact information (I don't want to post it here as a courtesy to him, for fear of spammers and the like). Incidentally, Tom Green (the maker of my primary flute) highly recommended his work to me when I purchased the instrument, without realizing I was already using him! He also is working in association with the American Flute Guild. I don't know where you're living, so I can't give any specific suggestions for local techs, but my opinion is that you should avoid sending it to Powell. The additional cost of shipping and insurance is something to consider, but also, Powell's repair department has many flutes going through it every day, which may mean that small details are missed when it comes to any one of them. That's one reason I prefer small, independent techs, as they have fewer flutes and can dedicate all their attention to each one. In the end, it's your call, of course.

it's worth it if the techie is a good one...

I highly recommend Tonya (I don't know her last name) at the Miyazawa Co. She works also on Powells as I stated earlier.

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One thing to consider is that at the Powell factory they only handle repairs on the top Handmade models and will tell you that you have to deal with repairs from the place that you bought your Powell from. I think that is pretty well.. uh.. snobby on their part personally. Not all of us can afford their handmade models, so we are less privilaged and don't get the same treatment? I love my Powell, but the company itself.. that is another matter.

if you may come up to NYC, my tech is Anne Pollock, www.yourfluteworks.com, there is also a good one in philly, but his name escapes me at the moment...

i didn't kno wmatinence for a flute cost so much,

what is a coa

Clean, Oil, & Adjust

Doesn't include repadding.

It does stand for Clean, Oil, and Adjust. Basically, the tech will take apart the mechanism, flush out any old oil and gunk that's built up, clean the flute, remove and replace the headjoint cork (if necessary), re-oil and reassemble the mechanism, and adjust it so that all the keys that work together perform as they should. Depending on the tech, some pad work or other "extras" might be included to be sure that it's in good shape. A COA should be performed annually (more often if you play heavily), and will help ensure that your instrument is in top playing condition between overhauls (which essentially put your flute in "as new" condition, and should be done once every 3-5 years).

i own a muramatsu and i pay nowhere NEAR $300 for a coa. however, im lucky that my technician knows my family and gives me a heck of a deal on anything i buy from the store. my yearly maint. fee is around $75