the 3rd gen Runners are from 96-02 model years. Rear axle seals and radiator failures in the auto tranny versions can be significant if ignored. Some owners suggest the 99-02 versions are a bit more comfortable- but the manual tranny 5 speed disappears after the 2000 model year, as does the 4 cylinder powered option.
As Jacket mentions a rear locker is a highly desirable option. The Limited versions have a few more creature comforts and center diff locking. However, Limiteds are always auto trannys and V6s. Power leather seats upgrade to heated in the 01-02 versions.
The axle seals are a cheap part but need addressed before they fail to prevent soiling the rear drum brakes. The auto tranny radiators should be replaced at approximately 8 years old to prevent the dreaded "strawberry milkshake" condition that contaminates the automatic tranny. Some owners favor an external tranny cooler and bypassing the factory cooler lines leading to and from the radiator.
Properly maintained- I would suggest an older 3rd gen Runner under 200K miles can be had for less than $5K. At miles higher than that-overdue care is almost a certainty for the ball joints and other front end suspension components.
T4R.org is Runner specific and Yota Tech is also helpful.