Kit Bashing is a great idea for a thread. Worthy of being a sticky as a resource.
There are lots of kit bashing sets for sale on the web but finding some quality free ones is not so easy. This one was a stand out for me - great quality and detail with 414 pieces.

Subject matter is Hard Surfaces: Hard Surface Kit Bash Pack 01.

I have some more, just need to find the links to them again.

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