That's a good point. If you get notification that the camera is triggered, and you check the video and see the camera is covered, then it would be safe to assume, it's not a Amazon delivery.
If his porch ceiling is higher than 7 feet, just mount the camera up at the ceiling line. Someone would have to grab a chair or ladder to cover the camera, and just like my first paragraph, you'll instantly know if it's Friend or Foe.
Plus, being tucked up at the ceiling line will help with glare and IR issues.
Case hardened or color case hardened? Am I missing something here? I also seriously doubt that you will ever get any ROI or even break even on a Smolt. The best is to buy one already built and let the original owner take the hit.
OTOH, I don't buy guns as an investment - they are a poor one - I buy them because I like them. Will they go up in value? Hopefully, but that's not the point.
If you are after a color case hardened gun, check out offerings from the S&W Heritage Series. Here's my Model 24-5 (.44 S&W Special)
The CCH on these was done by Doug Turnbull - the best in the business.