I'm a California LL and have a tenant who refuses to pay late fees for a four-day late payment that occurred in August. Tenant paid late only once. Late fees were agreed to in the One-year lease agreement that expires in five months. Everytime I remind tenant about the late fees, tenant goes ballistic. Lately, tenant has become abusive and is annoying me with nuisance requests to fix petty things. I'm a pretty good LL and respond to tenant's request for repairs within a reasonable period of time, depending on the seriousness of the problem. Of course, health and safety issues have priority. However, tenant and I disagree regarding what is "reasonable". Lately, Tenant has become very obnoxious and bossy, and treats me like I'm an employee. Tenant believes that establishing what is reasonable and habitable can only be determined by tenant and refuses to pay late fees because tenant was "inconvenienced". I think this tenant has some emotional issues (passive aggressive?) and I'm considering asking tenant to vacate at end of lease term. Can I deduct the unpaid late fees from the security deposit when tenant moves out or should I take action now? Someone advised that I should have deducted the late fee from the following month's rent payment and billed tenant for the "unpaid rent balance". Is this a good idea? Can I still do this after 2-3 months and follow-up with a Three Day Notice to Pay or Quit? How should I handle this?