Invisibility is going to be very popular with monsters who want to go out in the world.
As far as scrolls are concerned: Xeroxing them doesn't work. Carbon paper does, even on gray paper where the runes are barely visible for intellectual property reasons, and tracing a xeroxed copy also works fine; a simple spell takes about five minutes to make a stack of four. The spells are available in French and Spanish. There isn't a huge selection to start. But it's something.
They give Angela an after-school job tracing them according to demand so they have more time to discover additional runes and work out additional spells, and they put up fliers in the Avalon advertising a mail-order service.
Bella gets a car. It's a beat-up station wagon, but it works.
Bella has a small business, a vehicle, and a long-term career plan.
She sets about making arrangements to skip the eleventh grade, and Darren follows suit.
The two of them are adorably attached to each other. There is a lot of kissing. Savannah teases them a lot and Bella messes with her and Darren blushes.
By the time summer vacation starts, they have a stabilized price point, sufficient regular buyers, enough repertoire, and a nest egg of money that permit them to rent a small storefront and hire a teenage griffin to sell scrolls in the Avalon. They are on their way out (Savannah accompanying for kicks, Bella driving) to seal the deal and drop off a batch of inventory. Bright and early.
"Meh. I'll go with ice cream tree frog, it's already embedded into my head because it was pretty funny."
"That's why the charmingly random words. Conveniently, each password is also consistent in its poetic feet."
"All your words are one emphasized syllable. Mine all go dah-DAH-dah. And Darren's go DAH-dah."
"... Huh! Okay, that's weird jargon but now I understand what you're talking about."
"If you've ever heard about 'iambic pentameter' as in the thing Shakespeare does, similar deal - dah-DAH dah-DAH dah-DAH dah-DAH dah-DAH end of line."
"I think she just learned more from that than she has in several years of English class," marvels Darren.
Savannah sticks her tongue out at him, and then goes back to eating lots of ice cream.
"And now if you ever need to apply for a job in education if not-Hogwarts falls through, just tell them you taught my sister about iambic pentameter. They'll hire you on the spot."
"People might not believe you about it, actually, it's so unheard of. You might need to drag Savannah along to confirm it."
Darren laughs. "All right. Too bad, now no one will know your abilities." Snuggle, snuggle.
"Okay, I am going to go watch a movie. Bye, snugglebunnies."
Wave. Then she goes.
Fidget, fidget, oh look there's the return of shyness.
He laughs a little. "You know I'm pretty sure I've been in love with you for a while now, I just - didn't realize it."