I don't think the 124 weighs much more than the 123.
My 123 wagon outweighs my 124 sedan by about 400 lbs. My 124 sedan listed new for $39995 in 1999, according to the sticker.
Of course, I have no idea what it really sold for, but I doubt that it was discounted more than 5% or so.

It does feel like a larger car. I don't really think anyone needs to feel guilt.

It might be silly to pay $50K for a car, but to buy one for less than half that only five years later, and drive it for the next ten to twenty years.

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Semibodacious Transmogrifications a Specialty

1990 300D 2.5 Turbo sedan 171K (Rudolf)
1985 300D Turbo TD Wagon 219K (Remuda)

"Time flies like and arrow, yet fruit flies like a banana"
---Marx (Groucho)