Hi Al,congratulations on job (so far)welldone.
I,ve gone through most of your experiences,when my wife (Brigitte) and myself started renovating our house in gmünd beginning 35 years ago.
(objekt first mentioned/documented in 17th century)
First of all I destroyed the “..wooden boards with the hole in it…”
No treasures found at all, just dug in wornout tires und skeletons of christmastrees.
Born in gmünd therefore knowing all the professionals in gmünd and trebesing personally,
I faced no real problems.
Though your experiences with local professionals
sound familiar to us as I (we partly)lived in UK
Namibia, South Africa,Zimbabwe, Zambia,Mocambique,
Sharjah,Dubai and furnished our houses we lived in with local professionals.
In case you w`d like to see our house as it looks now, just click panoramaview gmünd pankratium.
It`s the yellow one with the painting/fresco in front.

with best wishes and good luck
rudi stallegger