Section 7(2)(e) in The Bihar Apartment Ownership Act, 2006
(e)disclose on reasonable notice or demand if the promoter is himself the builder, the prescribed particulars as respects the design and the materials to be used in the construction of the building, and if the promoter is not himself the builder disclose, on such notice or demand, all agreements entered into by him with the architects and contractors regarding the design, materials and construction of the buildings;