I think if the rig hasn't sold after 7 weeks your price is too high. In my experience, when its priced right you'll get several calls the first week. If after two weeks the interest drops way off, the price is still too high. I drop prices weekly at $50 intervals until the calls start again. Sometimes, braking even is the best you can do.
We've sold two trailers in the past 6 months, both sold the first week, and we got the haggling price we wanted. Both trailers were old ('85 & '98) but everything worked and both were immaculately clean. That was the first comment everybody had when they walked in.