Tribunal held that when the assessee firm failed to produce single document during course of survey proceedings and post survey inquiry to show source of investment which could not be treated as income of assessee firm then, vague statements giving estimated details without supporting evidence would not help case of assessee. Accordingly the reassessment is held to be justified .As regards the adoption of cost of construction .Matter is remanded . ( AY.2011-12, 2012-13)