I'm writing some homebrew stuff for my campaign setting, and I realized that I have a very poor understanding of how Scrolls work.

I've been reading online that Scrolls are always cast at the level of the spell on them, but is it possible to craft, for instance, a 3rd level scroll of Magic Missile, that shoots 3 missiles? or is the scroll required to be the minimum possible level of the spell?

What about potions? Are they always the lowest possible spell level? If so, then why would you make a scroll over a potion?

Scrolls can be of any spell and any level of that spell (so long as the spell can be upcast).  Potions are their own thing and don’t really have any connection to spells and don’t typically replicate spell effects unless they are homebrew content (although some have effects similar to spells). 

You can get or make scrolls of higher levels for spells but they remain at those levels... for example a 3rd level spell scroll of magic missile will always be a 3rd level spell scroll of 3rd level regardless of who is using it. (It would create 5 magic missiles.)

I forget what published adventure I was playing recently, but there was definitely a scroll provided that specified it was for an up-leveled spell,.... gah, wish i could remember the adventure/spell!

Thanks, that's really helpful!

I have a couple other questions.

If I make a Scroll of Cure Wounds and my Wisdom is 16, does the Scroll cure 1d8+3 wounds? Does it use the creator's casting stat? Does it use the caster's casting stat? or does it just ignore all of that?

If I make a scroll with a save DC, like... Disintegrate, is the DC equal to mine? or is it based on something else?

Also if you could point me to where in official material it talks about this sort of stuff, I'd be grateful.

https://www.dndbeyond.com/magic-items/spell-scroll

Ah, ok, so they're static based on scroll level. Thank you!

You can homebrew anything you like.

For Scrolls, I like to have them rolled and tied with a ribbon of a particular color, a particular color of sealing wax, and the "seal' of the wizard or temple that prepared the scroll.  The ribbon may be cut square, on a diagonal, pointed or forked to give more clues to its type or origin.

For potions, they have a particular color of liquid, sometimes very fluid and sometimes very sticky (like honey).  They are in bottles that are characteristic of potions, with thick glass.  They have a cork stopper sealed over in wax, with a piece of ribbon under the wax that helps open the potion in a hurry.  The color of the ribbon, and the color of the liquid and viscosity tell you what the potion is.  The color of the wax tells you who bottled the potion.  Fake potions are made by putting colored liquid in a potion bottle.

I was DMing Phandelver, and a few potions in the story are described with a specific appearance that can be used to help the party potentially discern what they're intended to be based on appearance. The most obvious example is a Potion of Invisibility, which appears to be an empty bottle but lifting it, the bottle clearly has the weight of a filled bottle, and shaking it produces a sloshing sound.