Watch for loose or wandering steering. Make sure there are no leaks from any of the hydraulic pumps. Make sure the water spray system works and that the spray pump isn't leaking. A pelican with an auto lube system is a big plus. Saves you from greasing the 49 zerks by hand. Check the conveyor belt to make sure its in decent shape with no rips in it. Also make sure that with the conveyor running, all the conveyor rolls are turning. With the hopper rolled out, check the conveyor frame for any bends or rusted spots. Also make sure the two speed pumps are working properly. Top speed should be around 20mph. If it only goes 8-10mph, then the drive pumps are bad. Parts for these beasts are very expensive. Maint. is a must. Hope this helps you some