When I took mine off last year I listed them for $40 on CL. Saw quite a few others selling for around the same price. Didn't get any response. Dropped my price to $30 - no response. Finally dropped the price to $20 and sold them.
With all the 4runners around here (CO) being used for off-road applications, there are lots of running boards for sale and not too many people who want them. Maybe if people in your neck of the woods are using 4runners more for mall-crawling there might be a higher demand but there just isn't that much demand here.