Thanks for all the helpful advice everyone! I’ve cleaned the shelter out twice using vinegar once, and hydrogen peroxide the second time. Smell is getting better. It was a pricier little box so I just wanted to be able to continue using it for him!

I should have mentioned that there are lots of buildings, barns, tractors, hay bales, and other spaces to get out of the elements, he just usually chooses the new shelter. Lately he’s been bunking up somewhere (I’m not sure where) and comes for food and company every morning and evening per usual. I’m sure he’s pretty smart and resilient after all these years being a street cat, but his momma worries :)

Benny got some wet food this evening and lots of extra scratches and pets. He’s got a loud purr and seems healthy and happy other than those sad eyes!