Any chance of lowering costs of the clanhall decor items or is there reason it's supposed to be absolutely redonkculosly expensive to decorate the Clanhall?

And maybe chests the cost seems to be pretty sevre since clan rent was tweaked.
I'm not looking to have it back to same point as before tweaks to rent but seems it should have a slight adjustment

Would it be possible to make a Hammer item that will allow you to reuse decorative items?

Hammer does not quite sound like the right word although I understand what you mean.

Chisel
Tool
Extractor
Forceps
Remover
Solvent
Mover
Separator
Digger
Excavator
?

Sky hook (construction worker inside joke)