A friend of the retailer suggested a business account with a building society, mentioning Nationwide in particular.
"It's free to pay in cash - they even give you interest - you can't go overdrawn and you get five free cheques a month.
"So we pay in cash all week," he adds, "and then we pay one cheque into Barclays. Barclays gets almost nothing out of me, which is incredibly satisfying!"
And Tony Harris, who runs Hawthorn Stores near Chippenham in Wiltshire and who has clearly studied the subject, called with a lengthy list of tips.
"I believe that all banks are being forced to get as much out of customers as possible," he says, "so customers should request a breakdown of charges so they can check for accuracy. Are the figures historical or not? If the takings are down then it should be reflected.
"Don't bank at a different bank to your own," he adds. "If you're with Barclays, don't put the money through Lloyds as they will pass on the charges and your charges will be higher.
"If customers have no other facilities such as loans or overdraft, then they should look at transferring their account to, say, Alliance & Leicester."
His tips go on. "See if suppliers will take cash. I pay about £1,000 a week in cash to small suppliers. And make sure you don't put any private bills, such as National Insurance, through your business account. And if the retailer in Shotton pays himself a couple of thousand pounds in cash instead of by cheque, that also reduces it."
Finally, a tip from my plumber (who happened to be here when I got the call and who has enough interesting opinions to qualify him to retrain as a London cabbie). "Tell them if they trade near a Bureau de Change to do a private deal. They always need cash and probably pay to have it delivered."