Hello!
I have built my 3d FDM printer myself and assembled and reassembled it quite a few times and did a lot of troubleshooting already;
I am able to drive to Frankfurt (Oder) from Vienna and stay there for up to 6 nights; I bring my own tools for repair , also a testboard (ramps) and many parts for diagnosing (e.g. thermistors, multimeter) if needed;
I enjoy working with 3d printers and I believe every 3d printer can be repaired in a decent amount of time with the correct tools!
I am looking forward to hear from you,
regards Benedikt