429.609.  Broker's lien attaches to commercial real estate when, notice to be filed in office of recorder, when — installment payments of compensation, notice recorded when — lease, claim for lien filed when. — A real estate broker's lien authorized by sections 429.600 to 429.627 attaches to the commercial real estate, or an interest in the commercial real estate, when:

  (1)  The real estate broker procures a person or entity ready, willing and able to purchase, lease or otherwise accept a conveyance of such property upon the terms set forth in the written agreement with the owner or terms otherwise acceptable to the owner or owner's agent, or the real estate broker is entitled to a fee or commission pursuant to a written agreement signed by the owner or the owner's agent; and

  (2)  The real estate broker records a notice of the lien in the office of the recorder of deeds of the county in which the real property, or any interest in the real property, is located, if such lien is filed prior to the actual conveyance or transfer of the commercial real estate subject to such real estate broker's lien, except that:

  (a)  If payment to a real estate broker is due in installments and a portion of the payment is due after the conveyance or transfer of the commercial real estate, any claim for a lien for installment payments due after the transfer or conveyance of such real estate may be recorded any time after the transfer or conveyance of the commercial real estate but must be recorded before the date on which the payment is due.  Such lien shall only be effective as a lien against the commercial real estate to the extent moneys are still owed to the transferor by the transferee.  A single claim for a lien recorded before the transfer or conveyance of the commercial real estate, claiming all moneys due under an installment payment agreement, is not valid or enforceable to the extent of the payments due after the transfer or conveyance.  The lien attaches for purposes of this paragraph when the claim for lien is recorded;

  (b)  In the case of a lease, the claim for lien must be recorded within ninety days after the date of occupancy or the date of rent commencement as stipulated in the lease, whichever is later, unless written notice of the intention to sign the lease is personally served on the real estate broker entitled to claim a lien at least ten days before the date of the intended signing of the lease, then the claim for lien must be recorded before the date indicated for the signing of the lease.  The lien attaches for purposes of this paragraph when the claim for lien is recorded; or

  (c)  If the real estate broker has a written agreement with a prospective buyer as provided in subsection 2 of section 429.605, then the lien attaches when the prospective buyer purchases or otherwise accepts a conveyance or transfer of the commercial real estate and records a notice of the lien within ninety days after the purchase or other conveyance or transfer to the buyer in the office of the recorder of deeds in the county in which the commercial real estate, or any interest in the commercial real estate, is located.