Storage, bugs, critters & unwanted guests

I've never been too worried about the frogs/toads I have here. Not sure which they are. YES, they definitely help with the insect population which is why I tend to leave them alone. However if you look at the places where they usually tend to sleep, you will see some nasty brown residue left behind. I know because I have 2 outdoor outlets around my house with he caps you can open/close. One has a broken tab & they love sleeping in there. You can see the brown sludge that forms in that box. I can only imagine what can happen to a camper that won't be used but once every 8-12 weeks or so.