(1) Upon the filing of a complaint alleging an unfair practice in a real estate transaction, the commission shall serve notice upon the aggrieved person acknowledging such filing and advising the aggrieved person of the time limits and choice of forums provided under RCW 49.60.230 and 49.60.2235.

(2) The staff shall, not later than ten days after such filing or the identification of an additional respondent under this subsection, serve on the respondent(s) a notice identifying the alleged unfair practice and advising such respondent of the procedural rights and obligations of respondents under this chapter, together with a copy of the complaint.

(a) A person who is not named as a respondent in the course of investigation may be joined as an additional or substitute respondent upon written notice in accordance with subsection (2) of this section.

(b) In addition to meeting the requirements of subsection (2) of this section, such notice shall state the basis for the commission's belief that the person to whom the notice is addressed is properly joined as a respondent.

(3) Each respondent may file an answer to a complaint not later than ten days after receipt of notice from the commission.

(4) Subsequent to the filing of a complaint alleging an unfair practice in a real estate transaction under RCW 49.60.222 through 49.60.225, the commission shall commence proceeding with respect to the complaint within thirty days after receipt of the complaint.

(5) The commission shall complete its investigation of an allegation of an unfair practice in a real estate transaction within one hundred days of filing a duly prepared and signed complaint with the commission, unless it is impracticable to do so.

(6) If the commission is unable to complete the investigation of the complaint within one hundred days of filing, commission staff will advise the parties in writing of the reasons for not completing the investigation in the time allotted.

(7) The commission shall make final administrative disposition of a complaint alleging an unfair practice in a real estate transaction within one year of the date of receipt of the complaint, unless it is impracticable to do so. If the commission is unable to do so, it shall notify the parties in writing of the reasons therefor.

(8) The commission may also investigate unfair practices in a real estate transaction to determine whether a complaint should be brought by the commission itself pursuant to RCW 49.60.230 (1)(b).