A municipality appropriating or otherwise acquiring property for public use may in furtherance of such public use appropriate or acquire an excess over that actually to be occupied by the improvement, and may sell such excess with such restrictions as shall be appropriate to preserve the improvement made. Bonds may be issued to supply the funds in whole or in part to pay for the excess property so appropriated or otherwise acquired, but said bonds shall be a lien only against the property so acquired for the improvement and excess, and they shall not be a liability of the municipality nor be included in any limitation of the bonded indebtedness of such municipality prescribed by law.