well you're stuck with the depreciation hit. Consider the depreciation a done deal, irreversable, and go from there.
What makes the most sense at this point? would the new (cheaper) car get better milage or cost less to insure?
I sure hear you on waking up one day wondering where all the money is and realizing I'd been squandering my resources. after a couple years of being car-lite (thinning the herd of cars & biking a LOT more), i finally have some savings!
Yer on the right track my friend
Cheers