I have a 2WD dually and have never needed 4WD in the 11 years and 50,000 miles I've driven it. I can carry 200 lbs. of fuel in place of the mechanical stuff that goes with 4WD, which is a much better use of my carrying capacity IMO. OTOH the truck is used 90 percent of the time to pull the trailer and rarely used in the winter.
I bought my truck to use, not to get rid of, so the resale value is of no concern to me. FWIW I could probably sell my 2001 Dodge Cummins dually for nearly what I paid for it 11 years ago.