For me it's very simple. Suits/jackets in 38-40 and pants in 30-36 sell fast and with very little price negotiation. Same thing on ebay. Honestly, I would not even consider getting stuff above 46, unless it was ordered from me. Pants above a 38 waist need to be either sold very cheaply or held onto forever. Interestingly enough, I also stopped selling anything in a 42L-44L as I only know one guy on this forum that is a 42L that regularly buys stuff. On ebay, 42-44L are non starters.
That's because 42Ls like me are built to ideal human proportion and consequently fawned over, gifted of abundant, finely constructed 42L (52L) garments by Kiton bought at retail at Bergdorf Goodman from the most attractive salespeople better than Louis. Boston.