might need some more info to determine that like hdd size and speed, processor, screen size and resolution or just the model number. i would say if its atleast an I series a couple 100
As the Old saying goes Dollar two-ninty-five (PS used by my late Uncle).
Joking aside, two factors:
1) Market for used laptops - small
2) Cost of equivalant Laptop Performance wise divided by 2, posibly divide by 3. A "New" i3 going for $400 is probably higher performance
If Dell consummer mode 3->4 years old would be a negaive, Positive if it is an enterprise model.
Highest value for an old laptop is to gift it to a relative. I gave a 1005ha Eepc with a fresh copy of win8 to my niece for Christmas that had been sitting unused in a closet for over a year. That was a cheep item to begin with but I'm 100% sure I got far more gratification from her loving it than I would have if I sold it even for the original purchase price.