Believe it or not, some people still write checks for large retail purchases. And even with all the new-fangled technology that gives consumers and retailers nearly instant access to account balances, there is still some mystery about just how some checks get approved or denied. Take, for example, the Best Buy customer in Ohio who had no problem with a $2,500 check, but who couldn’t get approval on a $320 check from the same store the next day.

This was the situation brought by a reader named CG to the Cleveland Plain Dealer’s Theresa Dixon Murray.

CG had used a check to pay for a $2,500 TV at Best Buy. The check was electronically cleared and the transaction went through without a hitch. But when CG returned the following day to buy a $320 stand for the pricey new TV, it was a no-go.

“A statement on the back of the check returned to me was from TeleCheck and stated that the check could not be accepted,” writes CG. “But there was more than $2,000 in the account.”

As Dixon Murray points out, this appears to be an issue with TeleCheck’s cloaked-in-secrecy approval process and not with Best Buy.

See, TeleCheck doesn’t look at a check-writer’s available balance when determining whether to approve or decline. If it had, then CG’s purchase would have sailed through. Instead, it weighs other potential risk factors and warning signs of check fraud, like how much is being spent, where is it being spent, and is the item being purchased a favorite of check-kiters?

What Dixon Murray suspects — and we agree with her — is that the $320 check wasn’t approved because of the $2,500 check. The fact that these are both relatively high-value purchases at the same store within a two-day period is probably enough to set off the auto-denier at TeleCheck.

This sometimes happens with debit and credit card companies, where the issuer will flag a purchase — especially an online transaction — if there are multiple expensive purchases in a short period of time. Of course, most card issuers have simple ways for you to resolve this immediately by calling customer service and verifying your identity and that you are indeed making those purchases.

With the TeleCheck example, the customer doesn’t even have any recourse at the store level, as this determination is all being done by a third party. So complaining or appealing to a manager gets you nowhere.

If you insist on writing checks, especially for several hundred or thousands of dollars, be prepared for being given a hard time, and be prepared to pay with plastic or cash in case that check isn’t accepted.

Want more consumer news? Visit our parent organization, Consumer Reports, for the latest on scams, recalls, and other consumer issues.