I just sold my DP on Friday. I listed it 2 times on ebay and once on Craig's list. I got several inquiries from both listings including 3 or 4 wanting to exchange for real estate. I sold it after all the listings had expired.
I sold the MH for the average retail price. Fortunately, I sold it in about 3 weeks time. I wish I knew the secret to selling a MH is a short period of time so I could share it with others looking to sell. The only thing I can say is make sure it is priced correctly, is exceptionally clean and include many pictures in any listings. Also, be willing to negotiate. Slightly reducing the price maybe worth it rather than having the MH set around for many months while it depreciates and costs you money for registration, insurance and, in some states like PA, annual inspection costs.