Waterdeep is the default 'newbie' town, where young characters get their feet and start collecting cash. Usually, these characters cannot travel as far or as safely as older characters. If you have an older character, that does not worry about bandits and other road hazards, please consider selling your loot in other areas before Waterdeep.
Doesn't bother us older characters much to travel to Tantras or Berdusk to sell that platemail armour, but thats 40 platinum not taken out of Waterdeep's economy could buy several items from that level 12 priest trying to afford their first weapon.
Just something to consider next time you're emptying your backpack folks.


