263. No public institution or private institution under agreement may, without having obtained prior authorization from the agency,(1) lease an immovable;
(2) grant a lease on, lend or otherwise permit a third person to use any of its immovables for a period exceeding one year;
(3) carry out construction, enlargement, development, conversion, demolition, reconstruction or major repair work on its immovables where the estimated total cost of the project is less than the amounts determined by regulation under subparagraph 3 of the first paragraph of section 505, except development, repair, improvement or maintenance work the cost of which is less than the amounts determined by the same regulation and which requires no borrowing for its financing.