Most utility corridors are in the middle of nowhere and already established (and people stay away because of this), so reusing an existing corridor is relatively easy - unless it widens into someone’s yard. Then it’s a matter of how much money that person has.
For connecting previously not connected areas with a new line, especially if it goes through somewhere folks are living? Be prepared for the actual work making whatever you are doing to be a tiny tiny percentage of the time and costs involved.