429.618.  Petition, content, parties' foreclosure action, procedure — liens having priority over broker's lien. — 1.  A petition filed pursuant to the provisions of this section and section 429.616 shall contain a statement of the terms of the contract or agreement on which the lien is based, the date when the contract or agreement was made, a description of the services performed, the amount due and unpaid, a description of the property that is subject to the lien and any other facts necessary for a full understanding of the rights of the parties.  The plaintiff shall file the action against all known parties who have an interest in such real estate.  A foreclosure action for a lien claimed pursuant to sections 429.600 to 429.630 shall be brought pursuant to the provisions of sections 443.190 to 443.280.

  2.  Valid prior recorded liens or mortgages shall have priority over a real estate broker's lien.