Hello!
My mom's '94 Pontiac Grand Prix is on its last legs. I just found out that two tires need to be replaced, and also that the car needs to be smogged soon and will likely not pass. She needs a car that can last another 4 or 5 years without becoming a serious financial burden. It needs to be an automatic

and has to get good fuel mileage. "Class" is not a real consideration here.
She's voiced that she wants a compact Japanese 4 cylinder car, but I think a 123 would be a better choice;
AFAIK they get roughly the same fuel mileage, diesel's cheaper than 87 gas by a fair margin, and as we all know, these engines are just about indestructible.

She has said that she can tolerate driving my car, but would prefer more power, so I don't think she'd even jokingly consider a 240D or even a 300D n/a, so if she went the Benz route, I'm under the assumption that a turbo 300D's the only real option here. I don't know how much she's willing or able to spend, but can anyone give a good argument either way? She originally wanted to buy a new Jetta (circumstances won't allow that now), and at first she adamantly didn't want a diesel, but before the new car idea got scrapped, I think I had convinced her to seriously consider a TDi.
I would have posted this as a poll, but I plan on showing her this thread, and I'm sure she'll want to see the logic behind the reasoning.
Thanks in advance!