Section 1804. Informal and simplified procedure on small claims

The court
  shall conduct hearings upon  small  claims  in  such  manner  as  to  do
  substantial  justice  between  the  parties  according  to  the rules of
  substantive law and shall not be bound by statutory provisions or  rules
  of   practice,   procedure,   pleading  or  evidence,  except  statutory
  provisions  relating   to   privileged   communications   and   personal
  transactions  or  communications with a decedent or mentally ill person.
  An itemized bill or invoice, receipted or marked paid, or  two  itemized
  estimates  for  services  or repairs, are admissible in evidence and are
  prima facie evidence of the  reasonable  value  and  necessity  of  such
  services  and  repairs.  Disclosure shall be unavailable in small claims
  procedure  except  upon  order  of  the  court  on  showing  of   proper
  circumstances.  In every small claims action, where the claim arises out
  of the conduct of the defendant's business at the hearing on the matter,
  the judge or arbitrator shall determine the appropriate state  or  local
  licensing  or  certifying  authority  and  any  business or professional
  association of which the defendant is a member. The provisions  of  this
  act  and  the  rules of this court, together with the statutes and rules
  governing supreme court practice, shall apply to  claims  brought  under
  this  article  so  far as the same can be made applicable and are not in
  conflict with the provisions of this article; in case of  conflict,  the
  provisions of this article shall control.