"Section 11.    Lands subject to purchase. — The Administration, acting for and on behalf of the Government, may negotiate to purchase any privately-owned agricultural land when the majority of the tenants therein or occupants thereof in case of abandoned land petition for such purchase."

"Section 16.    When proper. — The Administration may initiate and prosecute expropriation proceedings for the acquisition of private agricultural land subject to the provisions of section six, paragraph (2), upon petition of a majority of the tenants or occupants thereof in case of abandoned land and after it is convinced of the suitability of such land for subdivision into family-size farm units, and that public interest will be served by its immediate acquisition, when any of the following conditions exists: 

"(1)    That the landowner falling within the terms of section six, paragraph (2), continues to refuse to sell after all efforts have been exhausted by the Administration to negotiate for its purchase; or

"(2)    The landowner is willing to sell under sections eleven and twelve but cannot agree with the Administration as to the price and/or the manner of its payment."

"(3)    At cost — shall mean the purchase price plus six per cent interest per annum which includes the one per cent per annum for administration expenses, plus actual expenses for survey, subdivision and registration. The cost shall be paid on the basis of a twenty-five-year amortization plan.