§ 15. Sale of property. (a) Unless a greater percentage is provided for in the declaration or bylaws, and notwithstanding the provisions of Sections 13 and 14 hereof, a majority of the unit owners where the property contains 2 units, or not less than 66 2/3 % where the property contains three units, and not less than 75% where the property contains 4 or more units may, by affirmative vote at a meeting of unit owners duly called for such purpose, elect to sell the property. Such action shall be binding upon all unit owners, and it shall thereupon become the duty of every unit owner to execute and deliver such instruments and to perform all acts as in manner and form may be necessary to effect such sale, provided, however, that any unit owner who did not vote in favor of such action and who has filed written objection thereto with the manager or board of managers within 20 days after the date of the meeting at which such sale was approved shall be entitled to receive from the proceeds of such sale an amount equivalent to the value of his interest, as determined by a fair appraisal, less the amount of any unpaid assessments or charges due and owing from such unit owner.

(b) If there is a disagreement as to the value of the interest of a unit owner who did not vote in favor of the sale of the property, that unit owner shall have a right to designate an expert in appraisal or property valuation to represent him, in which case, the prospective purchaser of the property shall designate an expert in appraisal or property valuation to represent him, and both of these experts shall mutually designate a third expert in appraisal or property valuation. The 3 experts shall constitute a panel to determine by vote of at least 2 of the members of the panel, the value of that unit owner's interest in the property.