The prices noted by the thread starter are pretty standard for New York. I know nothing of Bhambi but if they are tailors, they may very well provide higher quality service than the many Dry Cleaning shops that also offer tailoring and alterations. These dry cleaning shops charge the same prices as regular tailors, but generally have someone who knows how to sew and could reattach buttons, but knows little about adjusting the seat of a pair of trousers or waist suppression on a coat.
By the way, we should clearly note that the thread started in 2005. Prices have gone up since then.