Sometimes simply thinking about what needs to be done while you are driving your vehicle every day can reveal a lot about what needs to be done when it is not being driven. Batteries die - thats it they just die. I can explain why and if you really want to know send me an email and I will tell ya. Just because you charge them the day before you pick up your vehicle does not mean they will stay that way. Batteries are made from lead and acid and sooner or later the acid wins.
Oil changing it BEFORE you STORE is much better than after. Used oil contains sulphuric acid not to mention a lot of other nasty stuff. The bottom line is leaving it in your crankcase and on the parts that need good lubrication when it comes time to start your vehicle is not good.
Heres a good one!!! Turn off the A/C!!! A/C compressors are finnicky things. I'm not sure why but I have seen more than one of them freeze up while a vehicle has been stored.
Ah then there's the coolant. Coolant just like you battery dies. It's a specific gravity thing. Have it changed.
This one I love - Laundry - Dont leave it in the vehicle. It just gets worse.
Oh I almost forgot the stereo!! turn is OFF!! Do not leave any electronic devices on or in the vehicle. ALL ITEMS LEFT IN A VEHICLE ARE AT YOUR OWN RISK INCLUDING ELECTRONICS.