Many standard leases or pet addenda include language stating that you can be charged $15 to $25 per day per animal for any violations of the pet agreements.
If you have more than a few snakes (lets say 10 for example) you could accrue $250 per day for the dates that they could establish they were present. You could end up thousands of dollars in debt very quickly. They might not try to collect, but you may have signed a legally binding document agreeing to pay this charge. A court would generally read it as written and assess the total fine.
It is much easier to come clean up front and make them understand that you don't keep venomous animals (if you do, good luck trying to find anywhere to rent!), that you don't breed rodents to feed them, and then you ought to be able to work something out.
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Chris Harrison
...he was beginning to realize he was the creature of a god that appreciated the discomfort of his worshippers - W. Somerset Maugham