In the winter of 2022 a friend of mine brought me this baby possum.
It was in the city and there was no sign of a mom or siblings.
I kept him until the Spring of 2023 and then I released him. 
Our property is wooded and has water so I let him go there.
About a week before I released him, I put his cage outside so he could acclimate.
Then when I felt like he was ready, I opened the door and let him go.
I kept his cage with food and water out for a week or so, then I put it away and just left food and water out for him.
We were still seeing him a couple of years later.
He would come looking for cat food and sometimes he would just hang out on the porch.
They have an extremely short lifespan so I'm not sure if he's still around but I feel like he had a pretty happy life.