purchase price For purposes of subparagraph (A), the minimum purchase price under this subparagraph is an amount equal to the sum of— (i) the principal amount of outstanding indebtedness secured by the building (other than indebtedness incurred within the 5-year period ending on the date of the sale to the tenants), and (ii) all Federal, State, and local taxes attributable to such sale. Except in the case of Federal income taxes, there shall not be taken into account under clause (ii) any additional tax attributable to the application of clause (ii). In the case of a purchase of a partnership interest, the minimum purchase price is an amount equal to such interest's ratable share of the amount determined under the first sentence of this subparagraph. (6) Treatment of rural projects For purposes of this section, in the case of any project for residential rental property located in a rural area (as defined in section 520 of the Housing Act of 1949), any income limitation measured by reference to area median gross income shall be measured by reference to the greater of area median gross income or national non-metropolitan median income. (7) Determination of whether building is Federally subsidized (A) In general Except as otherwise provided in this paragraph, for purposes of subsection (g)(1), a project shall be treated as Federally subsidized for any taxable year if, at any time during such taxable year or any prior taxable year, there is or was outstanding any obligation the interest on which is exempt from tax under section 103 the proceeds of which are or were used (directly or indirectly) with respect to such project or the operation thereof. (B) Special rule for subsidized construction financing Subparagraph (A) shall not apply to any tax-exempt obligation used to provide construction financing for any building if— (i) such obligation (when issued) identified the building for which the proceeds of such obligation would be used, and (ii) such obligation is redeemed before such building is placed in service.