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.
"I would not be dating you if you were not moral," points out Darren. "It's not actually just because I am dating you, it's because you are the sort of person I would date, and am, in fact, dating. I'm kind of picky. The numbers are kind of memorized, I was approximating them a bit, in my head they're more fluid. Besides, yours are pretty easy, I think about you a lot. If you wanted me to spit out the numbers for say, Mike, I would need time to think because I don't think about him very much."
Darren smiles and nuzzles back. "Also, your boyfriend is a nerd. I hope you're not surprised by this development."
"Not a bit. It's great."
He snickers. "Was it the math problems that made you think so?"
"Nope. I already thought it."
"Awww. Thanks." Snuggle.
Snuggle. "I am extremely fond of you, you may have noticed. And you are a huge nerd, so if it was a minus, I could not be nearly so fond of you."
He giggles and nuzzles her. "Thank you for loving me and my nerdy, nerdy ways."
"You are welcome."