This is covered under 22658(a)(1):
22658. (a) The owner or person in lawful possession of private
property, including an association of a common interest development
as defined in Section 1351 of the Civil Code, may cause the removal
of a vehicle parked on the property to a storage facility that meets
the requirements of subdivision (n) under any of the following
circumstances:
(1) There is displayed, in plain view at all entrances to the
property, a sign not less than 17 inches by 22 inches in size, with
lettering not less than one inch in height, prohibiting public
parking and indicating that vehicles will be removed at the owner's
expense, and containing the telephone number of the local traffic law
enforcement agency and the name and telephone number of each towing
company that is a party to a written general towing authorization
agreement with the owner or person in lawful possession of the
property. The sign may also indicate that a citation may also be
issued for the violation.
It must be posted at all entrances.
You might want to provide the manager with a copy of these subsections from 22658:
(e) (1) An owner or person in lawful possession of private
property, or an association of a common interest development, causing
the removal of a vehicle parked on that property is liable for
double the storage or towing charges whenever there has been a
failure to comply with paragraph (1), (2), or (3) of subdivision (a)
or to state the grounds for the removal of the vehicle if requested
by the legal or registered owner of the vehicle as required by
subdivision (f).
(2) A property owner or owner's agent or lessee who causes the
removal of a vehicle parked on that property pursuant to the
exemption set forth in subparagraph (A) of paragraph (1) of
subdivision (l) and fails to comply with that subdivision is guilty
of an infraction, punishable by a fine of one thousand dollars
($1,000).
The manager could be charged with an infraction (criminal offense) and would appear to be liable for double the storage fees. You can either call the police to enforce the infraction and PRAY that the responding officer is familiar with this subsection (which, I would very much doubt), or, you can threaten to take the management to small claims court.
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