In exercising its powers under s. 101.12, the department of safety and professional services or any city, village, town, or county may, within its discretion for proper cause shown, waive any particular requirements relating to public buildings, structures, grounds, works, and improvements imposed by law upon projects under this chapter; the requirements of s. 101.13 may not be waived, however. If, however, the prospective lessee so requests in writing, the authority shall, through the participating health institution, participating educational institution, participating nonprofit institution, or participating research institution as its agent, call for construction bids in such manner as is determined by the authority with the approval of the lessee.