Hi there 
just wanted to share with you this cool project.
I completely modeled the castle in Blender 2.79 from photos I took on site,
then exported the model in four parts for 3D-printing so it could be printed in wax.
Afterwards a goldsmith I am working with cast in in silver and gold and completed the hinges and lock mechanism. When you push on the gold heraldic tympanon, the castle opens.
It is like a piggy-bank, albeit not for pennies, but for Krügerrands 
it is around 15cm in length.
The final model was extremely large because of the shindle texture, I had to upgrade my RAM…there are over 10,8 million tris 
Just in case you want to know more about my workflow, I recently published my first class on Skillshare (the link includes 2 months of premium for free, cancelable anytime)
It is for beginners in 3D-modeling for printing. Feel free to check it out, if you’re interested! 