Sorry, but I disagree. They’re absolute shite & wear off in a day or two in my opinion. You need to get rid of the source of the stench by heavy cleaning, recleaning and then ozoning. Even then it won’t be 100% but a valet & an ozone does enough at my end of the market. Tbh the only way is to replace seats etc if they’ve been soaked in piss or immersed in a cloud of cannabis smoke for 3 years.
+1. Many are kept by nice normal people. However many are kept by parasitical scum who respect nothing because they are used to getting everything in life for free & live this f***ing pigs in a sty. When you give someone something for free they do not value it - just think of your kids leaving the lights on, that ain’t concerned about the electric bill