Publicly certified experts in Germany are officially sworn to act independently and impartially, appointed by the German chamber of commerce, provided practical experience and proven expertise in a subject (exceptional knowlegde in a dedicated field). In consequence their expert opinions can be trusted and relied upon. They never follow thridparty instructions unreflected when providing expert opinions including collections, appraisals, estimates, evaluations, investigation results or Statements on a testified status.
A proof resolution represents very often the guideline and range of the involvement (determines finally the scope of supply). Except a client order context defines all prerequisites and restrictions or constrains prior. The clients questions will be answered with an independent filter. Even answers with a share of responsibility of the client may be a result sometimes.
Moreover, anyone involving/commissioning a publicly certified expert strengthens his own position and reliability by freeing himself from the suspicion of bias or manipulation. It's precisely because publicly certified experts are controlled to be independent and impartial that the rules of procedure require German courts to call them to the expert witness status whenever an expert opinion required for a reliable and fair (appropriate) judgement, estimation and evaluation.
What you should expect: Founded estimation by sight in an experienced way, comprehensibly, competently, independently, impartially, correctly, exhaustively comprehensively and understandably.
Don't accept gobbledygook! Advice and Answers can help only if understood!