seamstress tipping. Please help

Hello:

I have no idea what is appropriate for seamstress tipping. I am going for my second fitting to Kleinfelds today and I was wondering if anyone has an advise of how much and if should I tip. Alterations there are $595

TIA

I have a difficult time understanding why brides do not want to tip the seamstress altering their dress.

All of this nonsense about how much alterations cost - that is the price set forth by the bridal salon. Do you really think that the seamstress will get $595 for altering one gown ? Unless the seamstress owns her own business, most of that $595 is going for operating costs and overhead.

Anyone else who is providing you with good service receives a tip.
Your hairdresser, manicurist, waxer all receive tips. Hotel maids get a tip, bellmen, taxi drivers. Waiters and waitresses, bartenders, the guy that delivers the pizza gets a tip.

Would it really be that bad to give your seamstress $25 or even $50 ?

Found this one a Wedding tipping Etiquette site:

Seamstress/dress fitter - Although it is not customary to tip your seamstress or dress fitter if you feel that they have made an extra special effort on your behalf then tip them between $15 - $30.