Of course it is! Although you can most certainly find a doctor to reshape the nose in the middle of your face for $4000, it is not the operation you should be concerned about, but the result you may live with for the rest of your life. A poorly done rhinoplasty, regardless of the price you pay in dollars, will be the most expensive procedure you ever have. Besides the cost of revisions (if the problem can be fixed) is the psychological cost, the anguish, the embarrassment, and other potential problems, which have no true dollar value attached.
My advice: Don't shop price, shop surgeon, and shop result. If you can't afford it now, either finance the part you cannot afford, or wait to have the procedure done until you can afford to have the surgeon you want perform the procedure.