I think a fantastic and easy idea would be that each home on arrival has a bin of age appropriate toys for the children. These toys could be swapped out once a month; turn them in, the team sanitizes them, and new bins are ready for pickup.
Our Sintra location EC has a library where kids can check books out but I would also include some books.
This would be so helpful so parents don't have to travel with so many toys, and refreshing them monthly would keep everyone excited.