Vehicle sat unused for two years

That's a problem if the 12v battery is disconnected whenever the car is parked. The whole point of keeping the switch closed is to maintain 12v to the car so that it can respond to remote door lock requests and maintain settings in volatile memory. If the relay is normally closed, then it doesn't work as a low voltage disconnect because it requires power to disconnect the battery when it gets low, which defeats the purpose of having a low voltage disconnect.

So the problem with a normally open relay is that it consumes too much power when the car is parked, and the problem of a normally closed relay is that it's pointless. Relays of any sort are a poor solution to accomplishing the goal of maintaining 12v power to a parked vehicle for as long as possible, while not significantly impacting how long the car can remain parked.

Disconnecting the 12v battery is a last resort option, meant to be used only to prevent permanent damage to it.

 

There's those manual switches too. Not sure where to mount one though. Preferably somewhere where you DON'T have to crawl through to the hatch. That's not an issue with 4th gen though; you guys get all the perks. Big negative, apart from hassle/inconvenience: all your settings get toasted. And the aforementioned loss of of smart key.