Regarding cat con cleaning, most people really overstate how fast the cats get dirty. Plus in my experience, the car only gets a noticeable performance and fuel economy drop after the cat is almost fully choked.
My old 2010 corollas cat got choked at around 210k Kms. The cat was never cleaned before. It was fully cleaned then and the car's performance and fuel economy got to the same level as just 1 day before it was fully choked and the performance and fuel economy were always the same or better than other lower mileage Corollas. Similarly in my other cars, even after 100k+ kms without any cat cleaning whatsoever, the car's performance and fuel economy stayed the same as brand new.
So yeah in my experience, frequently cleaning the cat is just a waste of money and if you wanna be very cautious, get it cleaned at like 100k Kms.