In order to perform his duties under this subtitle, the Commissioner may enter and inspect any unlicensed child or adult care operation with the consent of the owner or person in charge, or pursuant to a warrant. Administrative search warrants for inspections of child or adult care operations, based upon a petition demonstrating probable cause and supported by an affidavit, may be issued ex parte by any judge having authority to issue criminal warrants whose territorial jurisdiction includes the child or adult care operation to be inspected, if he is satisfied from the petition and affidavit that there is reasonable and probable cause for the inspection. The affidavit shall contain either a statement that consent to inspect has been sought and refused, or that facts and circumstances exist reasonably justifying the failure to seek such consent. Such facts may include, without limitation, past refusals to permit inspection or facts establishing reason to believe that seeking consent would provide an opportunity to conceal violations of statutes or regulations. Probable cause may be demonstrated by an affidavit showing probable cause to believe that the child or adult care operation is in violation of any provision of this subtitle or any regulation adopted pursuant to this subtitle, or upon a showing that the inspection is to be made pursuant to a reasonable administrative plan for the administration of this subtitle. The inspection of a child or adult care operation that has been the subject of a complaint pursuant to § 63.2-1728 shall have preeminent priority over any other inspections of child or adult care operations to be made by the Commissioner unless the complaint on its face or in the context of information known to the Commissioner discloses that the complaint has been brought to harass, to retaliate, or otherwise to achieve an improper purpose, and that the improper purpose casts serious doubt on the veracity of the complaint. After issuing a warrant under this section, the judge shall file the affidavit in the manner prescribed by § 19.2-54. Such warrant shall be executed and returned to the clerk of the circuit court of the city or county wherein the inspection was made.