Legal Question in Landlord & Tenant Law in California

It depends on the stage of eviction. It might be worthwhile for your daughter to ask for an accounting of the rent supposedly due. If the landlord already has filed a lawsuit, your daughter should file an answer within 5 days of being served that includes both a general denial and an affirmative defense that the rent has been paid. Then, when trial time comes, she could show the court copies of all of her negotiated rent checks that she obtains from her bank. If her rental agreement provides for it, she might even be awarded her attorney's fees. Many communities have tenant legal clinics. You might suggest to your daughter to seek out some legal assistance.