reupholster swan chair  

Know your upholsterer
Having recovered a number of mid century pieces over the years many are notiriously difficult. Others are quite simple. Saarinen chairs with the upholstered back will make you wish you'd bought them new. Brno chairs Knoll will TELL you are very difficult. That's bull. They come apart very neatly and it's just an L shaped frame to cover. The most important thing is find yourself a good upholsterer. Any good shop will be happy to give you a firm estimate if you send them good photos and dimensions of an unknown chair or just the name of a well known chair. They will also tell you how much fabric to buy. You can save a couple bucks if you get fabric yourself but don't skimp. Add $30-45 per yard for a good upholstery fabric. Add the upholstery estimate + fabric to the price of a used chair to know what it's really going to cost.

expensive
I have completed similar projects, and if cost is your concern - this is not the way to go. That being said, I have a friend who had two swan chairs re-upholstered cheaply in Chicago. It was a decent job, but certainly not perfect. He had them refinished for $650 each. I think that was a great deal given the diffiulty of getting the curves right on this piece. It should be noted that upholstering this chair proved so difficult in the 1950's that Fritz Hansen had to develop a new upholstering process they later patented. Make sure you find the best person you can because re-upholstering doesn't get much more difficult than this chair.

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Automotive people can do some difficult pieces..

I was wondering about that...
I have four Knoll Mandarin chairs that need to be reupholstered thanks to Jimmie Jo (the cat that enjoys claw sharpening)... Assumedly due to his working for Fiat and other car companies Sottsass designed the chairs using automobile "chainstitching" on the seat and back and auto lacquer on the arms... I've often thought auto reupholsterers would have more affinity to the redo process than furniture upholsterers... I'll take a chair to a great shop that has done work for me and let you know what they say... Thanks AZ for reminding me to add that to my list of "things to do"