Opossums are exceptionally good groomers. I can hear you thinking, "So? Why should I care?" You should and I'll tell you why.
I realize that we're still in the midst of an extended deep freeze here but believe it or not, spring really is coming. And with spring comes tick season. Ticks that carry Lyme disease. Nasty stuff, that. I recommend avoiding it if at all possible.
That's where possums, cute but nasty buggers that they are, come in. Being so fastidious, they gobble up an extremely high percentage of ticks that attempt to feast on them. As in every tick they eat is one less that will eventually find its way to you.
Ah, now you get it. So although I don't necessarily recommend that you invite them to nest under your porch it might not be such a bad thing if they live in your neighborhood. Keep areas they might decide to seek shelter in closed up and your trash out of reach and you can coexist, no problem. Unless you have neighbors like mine but that was a topic of an older blog.