As used in this article, “interested person” means an owner or any other person interested in any of the following:

Prior to the time fixed for the assessment hearing any interested person may appeal to the legislative body by briefly stating in writing the grounds of his appeal. Such appeal may be made upon any of the following grounds:

At the time set for hearing protests the legislative body shall hear and pass upon all protests so made.

Upon such appeal, the legislative body may:

After notice and hearing of assessment pursuant to this chapter all the decisions of the legislative body are conclusive upon all persons entitled to appeal, as to all errors and irregularities which it has power to avoid or remedy during the proceedings or at the hearing.

If the resolution of intention is actually published pursuant to this chapter, a court shall not invalidate any assessment, diagram, or proceedings prior to the assessment, for any informality, or other defect.