Discord is the best place for help for actual budget, it is very active

I can see the tire pressure of my truck though the app and I don’t pay for any Toyota subscriptions. The only thing I’m aware they lock behind a paywall in the app is remote start, but you can still do that from the key fob for free too.

On the newer vehicles they do also lock the navigation behind a paywall but you can just use CarPlay or android auto for free.

Yup, HomeKit can 100% work without internet. It’s a requirement of being HomeKit certified. I block internet access to all my HomeKit devices and they work just fine.