To answer the first question, a Log Book service is to be followed exactly by what's in the log book, if TSC 1 claimed they will do everything listed in the log book, which specifically says spark plugs, oil filter(and oil) and rotate and balance(this one is iffy, I don't recall it being a req after the 3 years), they must do them. If TSC 2 will do the service but wont include oil, spark plugs or tyres... LOL.. they're planning on driving the car in, inflating the tyres and giving it back to you for $280. They are simply trying to rip you off because you are a woman from what I can see as the things they won't do are the first and most vital things in a high KM service. In regards to your battery issue, it is apparent you do need a new battery, however the alternator is questionable, has it happened since? Do you get any suspicious lights in your dash? $170 for a battery is a bit steep to be honest with you, I'm under the impression NRMA Batteries would even be cheaper... But if you trust the service center by all means, rough range for a battery is between 100 to 150 to give you an idea. Hope this gives you a bit of a clearer idea of what you want to do. Just don't get sold by the second service center if they're literally not going to do anything to the car.