Cold weather inspection

I was inspecting a house the other day. I opened an access panel to the plumbing in the main bathroom. As I Looked down where the drain overflow went through the floor I noticed what looked like a hornets nest. When I went into the craw space and crawled back to the bathroom area I saw the largest hornets nest that I have ever seen. Thanks to the cold weather and maybe a skunk or something that tore into it the nest wasn't active. Safety note: before you craw into your tight craw space you may want to do a walk around during the daylight hours to see if there may be any bees flying in or out of your foundation, siding, or any small they may find a way to get into your craw (no pun intended). Do a walk around take a few minutes if you look calmly you may notice them flying in a line away or coming in like airplanes into an airport. In this case there was a concrete block that was removed to allow access to a plumbing main trunk. And there was a small gap where someone replaced it.