He glanced at the sort of street scene long consigned to Hong Kong's history books: amid a colonnaded row of shops, a youthful Mr Ng points proudly up at the sign above his store, while a teenager - now, incredibly, Ethan's grandfather - peeps out from the doorway.
Sam turned to Ethan hunched over the keyboard. "Do you really think this will work?" he asked.
Ethan attached the image to the e-mail he was sending to Ng's surviving family in America.
Then, before clicking "send", he looked at Sam and shrugged. "Well, we can't offer any more money."
Chan sat at his desk frowning over the two invoices from St Jude's International School. One covered the fees for his children, Gilbert and Charlotte, while the other requested his regular "donation" to the school's community outreach programme - which translated in Chan's mind into the community regularly reaching into his wallet and taking money out.
For some reason, a willingness to pay the exorbitant school fees didn't seem enough to win your children a place at St Jude's. They had to be smart, too. Given that, as Chan reluctantly had to admit, neither Charlotte nor Gilbert were the sharpest knives in the kitchen drawer, the school authorities had hinted that an additional show of generosity might be needed to "smooth" their applications.
Chan checked his calculator. There was just about enough in his bank accounts to cover these bills, but after that ...
He glanced nervously across his office to the scale model of the skyscraper that had, of late, absorbed all his time, energy and, most crucially, money. The soaring block of luxury flats and shops didn't yet exist, and never would unless he could gain control of the old building that currently occupied the site. And to do that he needed to buy the shop that had just come up for sale ...
His musings were interrupted by the phone.
"Well?" Chan snapped. "Have they accepted my offer?"
"Not yet," the property agent on the other end of the line told him. "And ... there has been another offer for the shop. From the old guy who currently rents it."
"What!" Chan howled in panic and confusion. "How on earth could he get the money together to ... How much did he bid?"
"Two million - half a million less than you. Don't worry, they're going to accept your offer. You'll hear later today, I'm sure."
Despite this, when Chan went back to writing his cheques, he was still fretting.
In a shaded corner of the playground, Maya watched as Ethan also fretted. As he anxiously checked his watch again, she put her arm around his shoulders. "Ethan, you've done everything you can."
"No, you, Sam and Jenny have done everything you can," he told her. "And Grandad and I are never going to forget it - however this turns out. I just wish I could have done more."
"But what else? You created a website to support your family and save your mum from working herself into an early grave. And now you're selling a chunk of the site to try and buy your grandad's shop."
"It's probably not going to be enough though, is it?"
"But you did your best. And if the money isn't used to buy the shop, then your family's financial independence is secured for years."
He looked at her for a moment, then shook his head.
"You're right," he told her with a smile. "And I go to a great school, with the best friends anybody could hope for, and I've got ... you."
As he leaned forward to kiss her, Sam appeared out of nowhere waving his smartphone. "Have I got news!" he yelled.
As he threaded his way through the crowds in Central, Mr Tai, Ethan's grandad, caught sight of his reflection in a shop window and grinned broadly. It was hard to believe that was him in the sharp suit and even harder to believe that their offer of HK$2 million for his shop - HK$500,000 lower than the highest bid - had been accepted.
In their e-mail, the sons of the late Mr Ng had explained that until they'd seen the old photographs that Sui-man had sent them, they'd never realised how much the shop had meant to their father. They were certain that he would have wanted to see the business, and the community that existed within, continue.
Grandad shook his head - young people just kept on surprising him these days. Although they had little chance of seeing their one million dollars again for many, many years, Sui-man's friends Sam and Jenny were willing to invest their share of the shamefacebook profits in his dusty old shop. And Sui-man's girlfriend, Maya - who he had insulted to her face - had dug up the information that had made all this possible.
He grinned again when he recalled his grandson stealing a kiss when he thought no one was watching. As long as people remembered there were some things more important than profit, there was hope for the world.
Then, with a jolt, Grandad remembered where he was going. Without the investor's signature on the contract to buy a HK$2 million share in the website, he was just daydreaming. And if he was daydreaming, he also wasn't paying attention to the need to keep shamefacebook's business secret. With one quick glance back he ducked into one of The Lanes.
"Click" went the shutter of the camera again. But in this shot, Tai was nowhere to be seen. The private detective cursed as he realised he'd lost him in the crowds.
"You lost him?" a furious Chan demanded, as he slammed his fist down on the series of photographs his paid spy had taken.
Not only had Chan failed in his bid to buy the shop, and thereby save the deal he'd staked everything on, he still had no idea where the HK$2 million for Tai's successful bid had come from.
They were interrupted by Charlotte, his daughter, who entered the study without knocking.
"Dad, can I have HK$500? We want to go to the ..."
She broke off as she recognised a familiar figure in one of the photos.
"Why have you got a picture of Ethan Tai? That idiot's in my class."
The detective followed her pointing finger. "But that's the old man's grandson."
Now Chan was completely dumbfounded. "How can he afford to go to such an expensive school as St Jude's?" he demanded of his daughter.
"He's on a scholarship."
Her father stared at her for a moment then, quietly at first, he began to chuckle. Soon he was clutching onto the edge of the table as he roared with laughter at the ridiculousness of it all ... his donations to the school had been paying for the education of the grandson of the man who was blocking his billion-dollar deal.
To be continued next term