I've been thinking of you both lately.
For the ads, does your area do indoor advertising spaces anywhere? Maybe it comes with where I am, semi-rural, bad weather, and a general lack of telephone poles near walkways, but I've seen several indoor bulletins around where people can post whatever. Just a big cork board or a wall people tape things to.
Maybe if there is this sort of thing where you live the ads would last longer? They aren't going to be ruined by weather and it's harder to vandalize something while a bunch of adults are going about their day 10 feet away.
I've seen them at my vet, in post offices, the university, grocery stores, a laundromat... just public spaces like that.
And people do post lost dogs on them all the time.