That isn't cheap. It keeps you above board, so that's worth its cost already, but offshoring is such a grey-area that it might not pay to even investigate it if you ever fell foul of any local regs. I once knew a Swede who successfully operated his business through a HK company, but how feasible that is now, and how well that fits into German regs is beyond me.

Your affairs sound so simple I'm surprised there isn't the equivalent of a low-cost, online-only type of accountant in Germany. Plenty of those here, at least, in GB.

My other thought was for you to enlist the help of a local to call around for quotes to confirm whether or not you are being quoted an "English premium".