My engineer cost €5,000 about 5 yrs back - all planning issues, outline and detailed drawings, alterations. House size 4000 sq ft.
The structural engineer cost €750.
A separate engineer cost €1,000 for the 6 site visits and certificate of compliance.
This compares with architect quotes which were in the region of 30 to 40 grand for the same.
The design was my own conception and was bespoke.
Of the shelf builds are would have been about half that price.
The engineer I used was experiences and had building nous so he specified something builders could actually work off of with out questions.