The hammer rang once. A spark jumped off the anvil and did not go out. It waited. They followed.

It was the first warm week of April, and the group chat had found a cottage.

There were four of them in the chat: Tara, and Jess from her English class, and Priyanka, who had sat next to her in maths since Year 7, and Mo, who had left school at sixteen to do an apprenticeship at the garage on the ring road and still came to everything. The chat was called EASTER OR BUST, and Jess had changed the picture to a photograph of a beach.

The cottage was by the sea, two hours away on the train. It had a red door, a garden with a wonky bench in it, a kitchen with a kettle shaped like a hen, and a view of the harbour from the upstairs window. It slept four. It cost five hundred and sixty pounds for four nights, Monday to Friday, in the second week of the holidays. The booking had to be paid by this Friday, or it would go to the next people on the list.

I'VE BOOKED IT IN MY HEAD ALREADY, Jess had written. IT'S PERFECT.

It is perfect, Priyanka had written. Is it a lot though?

I can only do Monday and Tuesday, Mo had written. Got the garage Wednesday. Sorry. Will bring a cake.

Tara read it all on the bus home. Then she got out the folded plan from her bag, the one she had kept since September. It was very soft now at the folds, and covered in pencil from every month of the year. At the top it still said £127.50 a month, every month, for the deposit. Lower down, in pencil from last week, it said Easter — £120 max.

She looked at the cottage. She looked at the number. She looked at Mo's message, and Priyanka's.

Nobody had said how they would share it.

She thought about saying something, and then about how awkward it would be, and then about how nice the kettle shaped like a hen was. She felt a small knot in her stomach that had nothing to do with the bus.

"I was going to say let's just split it four ways," Tara said.

She was at the back table of the Whetstone café, with the cottage open on her phone. Danya was there, eating a teacake. Across from them sat Ada, who designed games and house rules for her younger brothers and sisters, and who had once spent a whole summer holiday working out a fair way to share one games console between four children.

"I was going to say it like this," said Tara. "Five hundred and sixty, four people, a hundred and forty each. Simple. Nobody has to talk about it. Then I book it tonight and it's done."

She already had the message half typed. Let's just split it 4 ways = £140 each, I'll book it!! 🏖

It felt good. Equal sounded fair. And it meant not having to talk about money with her friends, which was the worst kind of talking.

Ada read the chat, scrolling up slowly, and then scrolled back down.

"Rules aren't wishes, they're incentives," said Ada. "Who made this rule?"

"It's not a rule," said Tara. "It's just splitting it."

"Splitting it four ways is a rule," said Ada. "So is splitting it by nights. So is everyone paying what they can. You're about to pick one. Who made the rule? Was it the people who use it?"

"Hm. It would be me," said Tara.

"And did you ask the others?"

"Says who that four ways isn't fair?" said Danya, through teacake. "It's the same for everyone."

"Nobody says it isn't," said Ada. "That's the point. Nobody's said anything. Ask the swimmers and the anglers together."

Tara looked at Mo's message. I can only do Monday and Tuesday.

"How do we know what the others think is fair?" Danya asked.

Nobody knew. That was the problem.

"Can I say one thing?" said Tara. "If I ask, it turns into an argument. People get weird about money."

"People get weird about money when they find out the rule afterwards," said Ada. "Design for how people actually behave. Write down the rules first. Then you've got something to talk about that isn't anybody."

Ada took a napkin and drew three columns.

"There are lots of ways to share a cost," Ada said. "These are the three people mostly use. One. Everybody pays the same. Two. Everybody pays for what they use. Three. Everybody pays what they can, and the ones who can pay more, do."

"Which one's fair?" said Danya.

"All of them," said Ada. "Sometimes. Equal is fair when everyone gets the same thing. By use is fair when people get different amounts. By what you can pay is fair when the point is everyone coming, and some people have less." She tapped the napkin. "None of them is the only fair one. The thing that makes one fair here is that all four of you agreed to it before anyone paid."

"So it's not about the number," said Tara slowly.

"It's about the number, too," said Ada. "But first it's about who chose it."

"How do you know?" said Danya.

"Because I got it wrong first," said Ada. "Two summers ago. One games console, four of us. I made a rota. An hour each, round and round, all day. Equal. Perfectly fair." She smiled. "It lasted until lunch on the first day."

"What happened?" said Tara.

"My little brother only liked one game, and it took ten minutes to load," said Ada. "So his hour was really fifty minutes. My sister had swimming every afternoon, so she lost her turn three days a week. And my other brother didn't even want an hour. He wanted twenty minutes, twice, and the rest of the time he wanted to watch. My equal rota was fair on paper and unfair to every single person using it." She shrugged. "And I'd made it without asking any of them. So when it went wrong, it was my rule that was wrong, and I was the one they were cross with."

"So what did you do?"

"I got everyone round the kitchen table and asked them," said Ada. "We argued for an hour. Then we made a new rule. It was messier. Swimming days got swapped. Loading time didn't count. My brother got his twenty minutes twice." She tapped the napkin again. "It was much less equal. And nobody broke it all summer, because everybody had been there when we made it. If keeping the rule costs more than breaking it, they'll break it. If they helped make it, it usually costs less to keep."

Tara looked at the group chat again. Four people. One holiday. No rule yet.

"So the first thing isn't the number," she said.

"The first thing is the table," said Ada. "Everyone round it, before the money."

Marcus came in with a coffee and an envelope. Marcus kept envelopes for everything, labelled in thick marker pen: BUS, LUNCH, BIRTHDAYS, ONE DAY. He had once refused to go to the cinema because the envelope said no.

He read the napkin. Then he took out a pencil.

"Give every pound a job," said Marcus. "Let's put each rule on paper, with real numbers. Then you'll know what you're choosing."

He wrote under the first column. Equal: £560 ÷ 4 = £140 each.

"Simple," said Marcus. "Now by use. How many nights is each person there?"

"Me, Jess and Priyanka are there all four nights," said Tara. "Mo's there two."

"So that's three people times four nights," said Marcus, writing. "Twelve. Plus Mo's two. Fourteen person-nights altogether. Five hundred and sixty divided by fourteen is forty pounds a person-night."

He wrote it in the second column. By nights: £40 a night. Four nights = £160. Mo, two nights = £80.

Tara looked at the two columns.

"So if we do it by nights, Mo pays eighty, and the rest of us pay a hundred and sixty," she said. "And if we do it equally, Mo pays a hundred and forty for two nights."

"Seventy pounds a night," said Danya. "For Mo. That's not fair."

"It's not fair if the rule's by use," said Ada. "It's perfectly fair if the rule's equal and he agreed to it. Mo might want to pay equal. He might think the cake's worth something."

"The cake is definitely worth something," said Danya.

Marcus left the third column empty. "That one I can't fill in," he said. "Only you four can."

Devon sat down at the end of the table. Devon answered almost every offer of anything with a question about Sundays, and he looked at Marcus's columns the way he looked at everything, as if each number were really a number of days.

"What does it cost you?" said Devon. "Not in money. In Saturdays."

Tara got out the folded plan and flattened it on the table. Devon read the line in last week's pencil. Easter — £120 max.

"So both rules are over your limit," said Devon. "A hundred and forty is twenty more. A hundred and sixty is forty more."

"Forty pounds is most of a Saturday at the bakery," said Tara. "Or a week of the deposit."

"Every yes is a no to something," said Devon. "Say what you'd be swapping. If you say yes to a hundred and sixty, you're swapping a Saturday you've already worked, or a bit of the flat."

"I could just pay it," said Tara. "And not say."

"You could," said Devon. "Then the plan's wrong and nobody knows. Or you could say your limit. The only person who can say it is you." He shrugged. "And the earlier you say it, the cheaper it is to say. Before Friday, it's one message. After Friday, it's a favour."

Tara's phone buzzed. It was a message, not in the group chat. Just to her.

hey is it ok if I say I can only do £120?? I really want to come but my mum said £120 and I feel so stupid saying it in front of everyone. pls don't tell them I asked

It was from Priyanka.

Tara read it twice. She put the phone face down on the napkin.

She thought about September, when she had nearly signed up to the climbing wall without reading the contract, and October, when she had nearly said yes to working every Sunday of her last year, and all the other months in between. Every one of them had started the same way: with Tara deciding something quietly, on her own, so that she would not have to say anything out loud. The folded plan was full of things she had nearly done quietly. And now here was Priyanka, doing exactly the same thing, and asking Tara to help her keep it quiet.

"Let me listen first," Tara said, before anyone could say anything else.

She took the napkin, with Ada's three columns and Marcus's numbers, and drew a line under it. Under the line she wrote three things: who chose the rule, what each rule costs each person, who hasn't said their limit.

The first was easy: nobody, yet. The second was on the napkin. The third took a moment. Me, she wrote. Then, after a pause, P, very small. Then Mo — did he?

She opened the group chat. It had moved on without her.

SO ARE WE BOOKING??, Jess had written. Equal split right?? £140 each? Let's not make it complicated, it's a holiday not a spreadsheet 😂 counting nights is so petty, we're all friends!!

Jess was not wrong, either. Tara had been on a trip in Year 9 where someone had worked out the bill to the penny, by who had chips and who hadn't, and it had ruined the whole evening.

I'm not paying for Weds and Thurs, Mo had written. Not being funny. I'm at work. I'd literally be paying for a bed I'm not in. I'll pay for my two nights and bring the cake.

Mo was not wrong either. He had a job and his own money and he knew exactly what it was worth.

Then her mum, who had seen the cottage over Tara's shoulder at breakfast, sent a message of her own.

Lovely! In our house we always split everything equally, then nobody can say it's unfair. Never had a single argument about it in twenty years. x

That was true too. Tara's family did always split equally. And there had never been an argument. Although there had never been a Mo.

She looked at Priyanka's message again, face down under her hand. I feel so stupid saying it in front of everyone.

"I think we missed someone," Tara said. "Me. I've got a limit too. I was going to pay a hundred and forty and not say anything, and then be cross about it all holiday. That's what I was actually going to do."

Nobody said anything for a moment.

"Who hasn't spoken yet?" said Danya. "That's what Track would ask."

"Me," said Tara. "And Priyanka. And she's asked me not to say."

The booking page was open on her phone. Complete booking — £560 — pay by Friday 12:00. Under it, the group chat, waiting. Jess's SO ARE WE BOOKING??. Mo's not paying for a bed I'm not in. Her mum's never had a single argument.

On the table in front of her was Ada's napkin with its three rules, and Marcus's numbers: £140 each, or £160, £160, £160 and £80. There was her folded plan, with Easter — £120 max in last week's pencil. There was Devon's question, what are you swapping?, and Ada's, who made the rule? And there was a phone face down on the napkin, with a message on it she had been asked to keep.

The cursor blinked in the group chat.

Everyone was waiting for Tara.

 

 

(Write the message Tara sends to the group chat before anyone pays.)

 

The spark dimmed to a warm dot and settled back on the anvil. The Green was just the Green again.

Back on the Green

That afternoon Lan, who was seven, was given a bag of twelve sweets to share with her two cousins.

She started to count them out, one each, round and round. Then she stopped, because her littlest cousin did not like the red ones, and her biggest cousin had already had sweets at lunch.

She asked them what the rule should be. They argued about it for a while. In the end they agreed that everyone got four, and the littlest could swap his red ones with anyone who wanted them.

It took longer than counting. Nobody cried.

Afterword. The idea in this case is fair division: there is more than one fair way to share a cost. Equal shares, shares by how much each person uses, and shares by what each person can afford are all real rules, and each feels fair in some situations and unfair in others. What usually makes a rule feel fair is not the rule itself but that everyone it affects agreed to it before the money was spent. The other half of the case is saying your own limit early: a limit said before the bill is one sentence, while a limit kept quiet becomes a resentment, or a favour asked later. You can practise designing rules that people will actually keep in CommonsForge, and planning what each pound is for in LedgerQuest.