Toyota Camry
Super reliable, decent mileage, good sized trunk and in your price range.
I bought a new one in 2003 for a work rig and better mileage than the fishing rig SUV. I can get a float tube in the trunk. The 4 banger has no problem cruising at 70 mph.
Approaching 100K with no problems other then routine service. It has 200K written all over it.