The party can pat each other on the back all they like but how does that do anything for their standing in the community at large?
Because they relate the exploits of others to NPCs, of course. Our parties usually have a bard, or a paladin, or both, very communicative folks. In our Odyssey of the Dragonlords, we have a ship full of NPCs including multiple bards, and the goddess of Music to do our PR, as Fame and Prestige are tracked stats.
It works as soon as a player in-character forces it to work, as follows:
Player-as-PC: "Hey, guys, I've got this extra magic sword. Falstaffe, you want it? Gimme 500 gold and it's yours!"
Falstaffe: "Thanks but no, I've got this enchanted mace which does me just fine. Never did get on with swords all that well."
PC: "OK. I wonder what I can sell it for in town?"
DM: "It has no monetary value."
PC: "Hell yes it does - I'll take it to the local mercenaries' hangout and offer it around, see what offers I can get for it. If nothing there I'll take it to the local temples, even to the palace if it comes to that. Someone's gotta want a magic sword badly enough to pay me for it - it's not like they grow on trees!"
"I'm sorry, I won't accept that estimate, the value from three people who are little bit more than brigands does not mean anything to adventurers like us".
And if the DM is playing at all in good faith she then has to determine what offers come the PC's way; and in so doing will set a value range for a sword of that enchantment. Lather-rinse-repeat with a bunch of other items and you might as well just build a list and have done with it.
Except that the principle of 5e (you might like it or not) is that there is simply no market for items, not enough items on the market, not enough buyers, not enough communication means and, even more importantly, not enough trust that it will not be stolen at one point or another.
This alone is why 5e's idea of magic items having no value is just plain dumb.
The designers and I don't agree. What gives you the impression that showing a sword to a few mercenaries will give you an estimate of the value of such specific items to high level adventurers ? It's just as dumb.
We have been running 5e for maybe 20 campaigns since we started, not one with monetary value for items, although there was trading, and it went absolutely fine.
Perhaps, but if it turns out that the first 5 magic items are all only usable by warriors don't the Rogues and Wizards have a right to their share of that?
And at the same time, none of our DMs are that one-sided and stupid, so we don't have that problem either.
And the answer is, damn right they do; even more so if as in my game they all have to pay for training each time they level up and thus are inevitably going to need that money.
That is a house rule, good for you if it works. As for ourselves, we have multiple ways to deal with this, in Odyssey of the Dragonlords, we all need money to get ingredients to reforge legendary weapons, and the world will end if we don't, so pooling the money for that takes priority over anything. In Avernus, gold almost does not matter, only souls and soul coins matter, etc.
Other motivations come and go but getting rich is always there either on the surface or not far beneath it.
Well, it's not the case at our tables, and we think our collective and collaborative play is much better for it (once more, not preventing discussions and dissenssions, but focussing on heroic things and plans).