At any time, the town shall have the power to borrow and to evidence such indebtedness by signing promissory notes. Such promissory notes shall be authorized by ordinance before being issued. The Council shall have the power to regulate all matters concerning the getting of promissory notes and shall not be required to solicit competitive bids upon the same, but shall be authorized to negotiate the best rate of interest available, privately, if the Council deems the same advisable.