1. six years is a good long term tenant 2. housekeeping is a gray area. some people live differently than others. If their lifestyle didn't bother neighbors OR create a hazard there's not much you can say. 3. six years is way too long without a rent raise 4. six years is way way too long without inspections. Had you had an insurance claim or especially a fire claim YOU WOULD HAVE HAD SOME S'PLAININ TA DO. and might have had the claim denied. 5. my opinion is they owe you nothing for the carpet. It was past it's useful life and replacement is on you. 6. IF conditions were indeed as bad as you said, they do owe you for a good general cleaning.--- BUT,... NOT LIKE AN OPERATING ROOM IN A HOSPITAL. 7. painting after 6 years is on you 8. APPLIANCES, FIXTURES CABinets -- gray area. I figure on spending a good chunk of money on this stuff every 10 to 15 years,.....with good tenants.
i BELIEVE a judge would look at a six year tenant favorably, irrespective of your hygiene claims.
your never inspecting your property or raising the rent will not speak well of you in court