Cat urine odor under hardwood floors

[Ethan Ross]

I have a rented apartment with hardwood floors. The previous owner had cats and there is a strong urine odor coming through the floors by the kitchen.

The tenant has tried applying a number of different deodorizes but all make the odor worse.

Is there anyways to eliminate or mask the odor without removing the hardwood floors?

Is it common for the tenant to ask for reimbursement for supplies they purchased due to the odor, or a discount off the rent due to the odor not being treatable?