Yeah I bought a good floor jack( pictured last page). The Jack stands are what are cheap. They are in the $20-$40 range it appears.
Honestly the best place to by jackstands is a tagsale. Just like Christmas tree stands. Save a ton of money + Generally the old ones are 40lb blocks of cast iron. The new ones are thin crappy metal.
None of the videos mention disabling the magnetic suspension before jacking and they all have MRC on their Camaro's. Don't think the system is active if the car is turned off. Will definitely look into.
I presume the magnetic suspensions don't have an issue as I believe they generally just tighten or loosen the shock absorption if I'm not mistaken. Air suspension is a different game when you have 2-4"+ of play in the ride height.
Maybe practice changing the oil on your Saturn? It's not rocket science. Frankly though if your dealer has never messed up your Saturn, they probably won't mess up your new car. Generally different cars have different oil capacities, especially higher in higher performance cars. I wouldn't be too concerned. It's never a bad idea to check your oil level 1. regularly 2. after dealer oil changes to ensure proper maintenance. If they missed out on 2L of oil it wouldn't be hard to notice checking the oil which you should be doing anyways.
I think you're vastly over worrying about this. Just buy the car already and enjoy it!