Statics for L-shaped stones?

Hello, do I need a structural calculation from a certified structural engineer for a retaining wall (load case 1) made of L-shaped stones, and if so, how much will it approximately cost??? Almost all manufacturers (e.g. EHL) already have technical documents and corresponding calculations for the load cases defined and provided for their L-shaped stones. The background of the question: I have to submit a building application because of [Außenbereich]...

Good question. I would generally interpret the technical specifications from the manufacturers as "Typenstatik," but whether that is sufficient in individual cases, I am not sure.

there I am at a loss.

Why do you even answer?

Why do you even reply?

So that my biggest fan can like that my second biggest fan is asking me that. This in turn is so logical that your question must be purely "rhetorical." And who replies anyway? - well, me :-)