Catalytic converter and transmission costs come nowhere near that of a new battery. As far as engines go, you can almost always repair an engine at a fraction

Catalytic converter and transmission costs come nowhere near that of a new battery. As far as engines go, you can almost always repair an engine at a fraction of the cost of replacing an engine. Multiple times if need be. Probably same with the transmission. Battery replacement is a one shot deal. Rust isn't a big deal where I live. I put 440,000 km on my 2001 Honda Civic and had it for 15 years. The body was still in good condition.