Oxidation/rust of engine parts in 2017 Yaris

[jowii]

Hello everybody! This is my first post here. Hoping to become a Yaris owner I hope this is the correct place to post this.

I am looking to buy a used 2017 Toyota Yaris Hatchback from Hertz.

I plan to take it to a mechanic as soon as I can before I decide to buy, but hoping to possibly clear my mind of some worry in the meantime (trying to remain optimistic because I really like this car). It has a few miles left on the basic warranty and 20 thousand or so left on the powertrain warranty.

I found what I consider to be an unusual amount of rust under the hood for a two year old car (images attached). They regularly maintain these vehicles, so I would think that if there was a huge concern, they would have addressed it...? You can't pop open the hood to do anything and not see it. Although I would think that clearing rust is something important to maintaining the vehicle as well.

The car otherwise runs really well and is in great shape. I won't be able to get a really good look at the undercarriage until I have a mechanic lift it. I know some metal parts can oxidize very easily with any amount of moisture and/or salt. Also this car originated from the northeast US...

I'm hoping that this is a sign of some parts that oxidize easily and not a sign of something worse. Parts towards the bottom of the engine bay don't seem to be rusted at all (from what I can see), it's more towards the top. Could this just be normal reaction to driving in coastal areas, humid areas, salt treated streets, etc.? Maybe someone let a little moisture get in with the hood open and that was enough?

Aside from letting moisture directly in, does enough moisture, such as driving in heavy rain or behind a traffic on the interstate, get in through the grille or bottom to cause this? Mostly, I guess I'm looking for answers that this may be caused by less severe things than driving through high water...

Thanks in advance! I'm hoping this turns out to be a non-issue and just needs a good cleaning. And I'm looking forward to becoming a Yaris owner and hanging out here. Looks like you all have a great community