Kernrechtsfrage
Whether the appeal could rely on a new final statement/invoice not filed below
Extrahierter Entscheid
The new document was inadmissible because the appellant already had reason and opportunity to file it in the cantonal proceedings.
Extrahierte Begründung
Under Art. 99(1) BGG, new facts and evidence are only admissible if the lower-court decision itself gave rise to them. The document concerned the very existence of the alleged fee agreement, which was already the central issue below.