They are not alone, but there are not that common either. And even when two parties meet, there can possibly be trade, but it's very different from having shops around the corner.
Well, I usually go by the genre, and they might go to an arena for fighters, or try to find a thief in a thieves' guild if they know where one is, or maybe to a seedy part of town, but there are no "adventurers halls" where you can shop for adventurers of any level when you need one.
There's two places where adventurers would logically tend to gather:
1 - Wth a few exceptions (Rangers being the most obvious) each class tends to congregate somewhere: Monks at monasteries, Clerics and Paladins at temples, Bards at colleges, Mages and Rogues at guilds suitable to their subclass, and warrior-types at mercenaries' halls or arenas.
2 - the legendary "taverns" where parties meet and form and then head out into the field.
And it's not like whatever level of whatever class of adventurer is going to be available and-or willing to join you: the results are always random. But it is more likely that places like this - particularly the (trusted) temples and mages' guilds -
will end up acting as clearing-houses for magic items that their members don't need but don't have the time to spend on selling them.
The thing is that there are no such places. Are there such places in published settings ? I don't think it's the case, even in the FR. Maybe Eberron, but even when we play there, we can easily get consumables or low level items, but not much more.
Thieves' and Assassins' guilds, and Bard colleges, have been in place since at least 1e. Temples and monasteries pre-date that. Mages' and mercenaries' guilds might have appeared somewhere but even fi not they're a logical thing for a setting to have.
First, we don't use artificers, and second I'm not sure that artificers can craft any item they want (at what level do they get that feature ?) and know the cost.
Then who makes the magic items? Also, isn't Artificer a class in 5e?
Look, at this stage, I think it just shows that we have very different views about the magic item trade in the settings. I like the 5e approach that there might be some trading if you let people know that you are interested in buying, it might get to the right ear and someone might contact you. But there is as high a likelihood that someone will come to try and steal it or scam you. These are powerful items and they attract powerful nasty people. And while I agree that people will trade anything if they can, they also have to protect their business, assuming that they can even make one, because it requires so much investment and it's so risky. The way I see it, magic items shops just cannot survive, what protection can they buy that will prevent powerful adventurers and thieves from stealing from them ? Who can they even hire to protect themselves ? They would have to be powerful adventurers, and adventurers are not interested in protecting magic shops. And actually, they might actually steal from the shop rather than guarding it.
I guess one thing I'd better clarify is that I'm not at all advocating for "magic shops" where you walk in and there's a rack of +1 weapons on one wall and a shelf of potions on another. I'm not a fan of that.
What I am advocating for is the logical and predictable outcome of a setting where adventurers are fairly regularly acquiring, disposing of, and in some cases building magic items: there's gonna be trade in them. Much of that trade will be between private individuals; some will involve a third party as a go-between, brokerage, or clearing house; and some will involve larger entities e.g. a trade between two guilds. Rarely, a high-end pawnshop might wind up with a magic item. Perhaps the only case where there'd be a bunch of stuff for sale all at once would be the estate sale of a rich ex-adventurer who had just died of old age.
When a party gets to town in my game, ask for a shopping list, and I run my randomized spreadsheet and tell them what happens to be available right now, those items aren't all being sold at the same place! The list is simply what the PCs can find out about fairly easily via inquiring at the most common places - temples, mage guilds, local adventuring contacts, and so on - but if there's fifteen things on the list they're probably being sold at twelve different places by as many different people or guilds.
Now and then, there might be a powerful wizard selling his production (and able to protect himself to some degree), but wouldn't it be better for him to create things for his own use or his own research ? If he's that powerful, he is very probably rich enough to not needing to sell off items.
Some people just like making stuff.
Actually, our DMs are way better than this (
) they are arbiters of fun, not only of nitpicking monetary rewards and magic items value, because that is absolutely meaningless to some people and some characters, whereas fun is important to everyone who comes playing the game.
What I mean here is that our philosophy is that there are many imbalances in a TTRPG that the system cannot compensate, in particular because the players themselves are imbalanced their capabilities and what they expect from the game. So we think it's better for a DM to balance the fun that people are having, even if it means giving different people different things depending on what they expect. This in turn means that while some people might be interested by money or items, others are not, so some people find riches and others find fame and story, and there is no universal coinage to balance this apart from fun.
Not sure if I'm clear, though...
I think I see what you're getting at. I guess I'm less willing to sacrifice realism on the altar of fun, in that I expect the treasure in an adventure (along with everything else in the adventure!) to be exactly the same regardless of what we happen to take in there as PCs; and if we take an all-mage party into an adventure where 90+% of the treasure consists of enchanted heavy armour and big weapons then so be it - we pulled the short straw this time, and it's up to us to find a way to turn it all into coinage or things we can use once back in town.
Which is fine, but 1e was a long time ago...
5e has training-to-level as an optional, I believe. I don't recall if 4e had any provision for training; if it didn't it's the only edition thus far to not even have it as an option.
