They absolutely won't be paying you any extra money for those heated seats... they're already going to have to go pay BMW for the freaking subscription anyways.

At best you could argue you're slightly increasing the interested market for your car, but even that feels incredibly flimsy. The market for used cars is vibrant, and very rarely is trim level a deciding factor on used car purchases.

Usually you can negotiate price on trim - but this decidedly removes that option. You just get fucked right round as the original buyer.