Where the Parties are agreed, a single Expert may be appointed. In some cases Courts ask that the Experts acting for the Parties meet together to establish any common grounds between their CPR35 reports.
It is not infrequent for barristers and insurers to ask for virtual conferences. Where I am appointed, no extra charge is made.
Culpable and Liable sound interchangeable but operate in separate legal frameworks. Mis-using Culpability or Liability can demolish a defence strategy or void an insurance claim or cover. Culpability answers the moral question "is blame deserved" and exists within criminal codes. In my experience Culpability Reports are rare compared with assessments of liability.
Appearances would normally be scheduled well in advance and are covered by time charges.
Local Authorities may be faced with Enforcement Procedures in relation to unsafe facilities particularly in relation to supervision and boundary conditions. Expert Witness Reports are commissioned to allow both the Local Authority and the Club / Operator to understand the issues and may involve some redesign options all of which would be set out in the initial proposal.
I maintain a large library of technical information which is available as a resource during the preparation of reports.