Just read in the online version of the Main Post
"Expertise and examination of the drilling notification can cost between 75 and 1300 euros according to the experience of the authorities.
Additionally: a specialist company must carry out the drilling. That costs between 8000 and 20,000 euros, says well driller and graduate geographer Stefan Schmitt from Haßfurt. The deeper and more complex the drilling, the more expensive. More effort arises, for example, if steel pipes have to be installed for stabilization during the drilling."
The price range is intense. Without an offer tailored to your circumstances, drilling costs are guesswork.