Sure.
But are those the majority of the magic items out there? And, indeed, do active adventures really represent the majority of demand for items beyond what they themselves find in the field?
It can or cannot.
But it doesn't matter, because the only pricing adventurous care about are adventuring items and adventurer items, typically not the same ones that nonadventurer want.
Nobility are likely to look for four types of magic items: defensive (self or area), useful-to-role (e.g. translation, communication, or persuasion/appearance-enhancing devices), functional (e.g. items that heat your castle, or allow or enhance long-range travel, etc.), or vanity (e.g. items as trophies or "just because I can"). The non-noble rich - which can easily include retired adventurers! - could well compete for items in the latter two of these categories.
Yes, but though a lot of those are not in the economy of a current adventurer.
Self-defense, end adventure utility items would be high cost for a setting with a strong adventurer community.
But vanity items and everyday functional utility items will not be high of adventurers.
A noble might spend a bunch of money on a broom that sweeps his castle. But a what elf ranger who mostly stays in there big treehouse in some forest somewhere or an adventure has little use for in animated broom.
Same thing, like my friend who doesn't DM. A DM book could be $5. He's still not buying it.
Its supply demand and cost. The reality is the magic item that would be most valuable. 2 adventurers that they would pour their treasure hoard into would be items that for the most part, only adventurers, adventurer killers, and assassination target bodyguards would buy.
It still costs X-amount to make (or commission) such a glaive, however, and that sets its base price
Yup, most items would be sold as the cost of creation plus the GP the seller wants to make while covering NP.
And that GP would be based on supply and demand.
And for most settings, especially how Dean D is based the demand for magic? Items is rather low dust, making the actual gold. And precious materials, the main resource of treasure.
It's like art pieces as treasure. Fardnard the fighter doesn't really want the painting. He got in the dead dragon's horde for himself. It's for the wealthy person, he's selling it to.
But if he finds a magic rapier, he might sell it to another adventurer, since Farnard is a strength based great weapon user.
Heck, if you're not an adventurer, nobles might not even want magic weapons and magic armor out of fair of evil adventurers breaking into their homes and stealing it and killing them. Good old rob the shopkeep.
Adventurers would dungeon delves to get better items in order to qualify for scary dungeons to get more gold or quest rewards.