Probably a good idea on the opossum. Live trapping is a cool thing.
Glad you were able to fix your cats. We had one black momma cat for years...never got pregnant. I guess some old Tom found his way over and that was the end of that. A few years later we were covered up. Those cats would be laying all about but the second you twisted the door knob they vanished like a fart in a whirlwind. I guess we could have spend the time trapping them but then what would we do with them? Couldn't afford to have them all fixed. Take em to the Human shelter and they would have been gassed anyway.
So I figured what would be more humane...cage em in a strange place until they got gased or suffocated...a miserable way to go...or just put a .22 in their heads as they were frolicking around their known and safe feeling home base. They'd be all content and happy one second and the next they'd be talking to the cat god. I opted for the .22 solution.