Is money taken in exchange for building an enclosure for stray animals that damage crops permissible or forbidden?

If "stray animals" refers to lost animals, then if they are young and cannot defend themselves against small predators, the one who finds them has the choice between eating them, keeping them for their owner and spending on them, or selling them and keeping the price. They have the right to claim back from the owner whatever expenses they incurred. However, if they are large livestock and can defend themselves against small predators, they do not fall under the ruling of a found item (luqata). But if it is customary to keep them in an enclosure to prevent them from harming people and to claim back the costs from their owners, then there is no harm in that.

And if "stray animals" refers to animals that their owners send out to graze in permissible pastures, then if they send them out during the day and keep them at night, no one is allowed to prevent them from grazing, and it is incumbent upon the farmers to protect their crops during the day. However, if they go out at night, their owners are liable for what they spoil. And if they go out day and night and there is no way to prevent them from spoiling crops except by keeping them in an enclosure, then this is permissible, and the keeper has the right to claim back the costs from their owners, because they have fulfilled the duty of safeguarding on their behalf. All of this applies to places where there are farms and pastures. As for places that are farms and have no pastures, the owners of the animals are liable for what they spoil, whether by night or day, and people are allowed to keep them in an enclosure and claim back the costs from their owners.