I am sorry to hear about your disappointment with the results of the breast surgery. Policy regarding coverage of expenses for revisionary surgery will vary from office to office and probably on a case-by-case basis as well. Costs of revisionary surgery may range from zero, to anesthesia/surgery center fees, to discounted surgeon's fees.
Generally, successful plastic surgeons rely on positive word-of-mouth and will work hard to maintain satisfied patients. Also, generally speaking, I suggest patients communicate their concerns in a calm and constructive fashion; this form communication tends to be much more effective than confrontational communication.
Best wishes; hopefully through courteous/respectful communication you and your plastic surgeon will be able to work out a plan to achieve your goals.