I’ve got you. So there are two things you need to understand.
Official magic items are probably THE worst balanced and designed thing in 5e. It’s like WotC didn’t really want them to be part of the game and REALLY didn’t want you to be able to craft them. Official item balancing is complete trash and should be wholly ignored, including rarity tags. (Case in point: Ring of Warmth [Uncommon] is a directly better Ring of Cold Resistance [Rare], Flametongue is Rare while Frostbrand is Very Rare, Ioun Stones suck major dick, etc)
The most important thing for pricing your magic items is to ask how much a plain +1, +2, and +3 weapon costs. Those are very basic items with clearly defined power levels, and you can determine the value of other items by comparing them to those basic weapons. In my games, a +1 weapon is 500gp, a +2 weapon is 6,000gp, and a +3 weapon is 80,000gp. That means that not only can I give all my other items fair prices, but if I compare my pricing to say, OneDnD where a +1 weapon costs 800gp, then that means I know that to maintain intended balance for a OneDnD adventure I should increase all prices by 60% (One of my friends runs the OneDnD prices for their low magic world, so this trick can be really helpful).
Anyways that document there has about 200 items that I’ve been making whenever I’m bored, so feel free to look around and steal some stuff.