Its not like you start the car with the aircon running, stezza playing, lights on, and gerge forman frying in the back seat. Get an uprated battery that fits in the old space and has the terminals in the correct places. If you go too big you are just wasting money. Too small, it wont last as long, even if it will start the car. To ke30 ke35 ke55, I have to agree with rollaboy. Accessories have nothing to do with it really, unless you go as far as a 4wd fanatic would, and fit car fridges, jacks, winches, airbags, spotlights and compressors etc. Then you would go to a dual battery setup.