Rooms without carpeting, and non-refundable pet fees. Vinyl flooring makes cleaning up after pets trivial. The only issue you have is soiling of upholstery and potential chewing. But if everyone pays a $100 per dog fee, only a subset of those dog owners will cause any issues so the good dogs subsidize the cost for the bad dogs.
The fee and deposits sound steep, until you compare them with the astronomical costs of dog boarding.