Well... Any Sedan basically? My family has 2 Camrys and they're both sturdy with 4 star crash safety ratings I think, have never broken down. Its also quite fuel efficient. If you have the money, buy a Camry Hybrid they're comfortable, very quiet especially if you're only using the electric engine (very good for drive by shootings - anyone get this reference?), definitely not a guzzler, I've almost gotten to 50mpg at the end of a tank; this isn't driving slow all the time either, of course you have to be generally patient, but you can still floor it a little.
Or did 4d mean 4 door?.. then I got no advice for you
I just read 40k.
The Camry Hybrid I have was 30k (paid in full) it has full leather interior, gps built in, moon roof, heated seats, and a something put on all the carpets and seats so that the car won't get dirty easy, and a similar thing on the body that helps prevents dents (like the leather thing you see on the front of cars, except clear. Of you could get the Toyota SUV Hybrid or the Lexus RX### Hybrid SUV; both will be more expensive, but you seem to have the money.