What are the conditions for a valid marriage, and when does a woman have a guardian, and what is meant by "declaration" (ishhar), and what is the fatwa regarding عرفي (urfi) marriage, and who attends the marriage contract assembly?

Marriage must be conducted with a guardian (wali) for the woman, whether she is a virgin or previously married. The most rightful guardians are the father, then the son, then the paternal grandfather, and so on, with the closest male agnate (asabah) having precedence. If there is no guardian, then the ruler is the guardian for one who has no guardian. Marriage must be publicized and announced, and this is done in the presence of the husband and the guardian, or their proxies, and two just Muslim witnesses. More than this number is preferable, due to the desirability of publicizing the marriage.