Wells Fargo's unauthorized account scandal has so far cost the bank $100 million in fines plus restitution and caused incalculable damage to its reputation. But it also serves up an often overlooked question for consumers. How many accounts and how many banking relationships should one have?

In an online, instant-approval world where it takes literally seconds to open a new bank account, an individual can end up consciously opening multiple accounts and establishing relationships with several different institutions.

The answer depends on individual circumstances, family lifestyle and needs, experts say, but a few considerations are worth pondering. Depending on each family's situation and needs, some couples may each have separate checking and savings accounts as well as a joint account, and small business owners may keep separate accounts for ease of record keeping. But each additional account can carry additional fees.

While opening additional credit cards or deposit accounts to receive a one-time discount or capture an attractive interest rate may make financial sense in some cases, Jason Kley, senior wealth adviser for Carlson Capital and director of financial education for the Financial Planning Association of Minnesota, said it is important to ask: "What is the purpose and does that purpose outweigh potential costs?"

And the costs are not just in direct fees, but added complexity and risk, he said. While software tools can help consumers track multiple accounts, Kley points to growing cyber security threats and risk of identity theft as potential pitfalls to having multiple accounts at several institutions.

"As a consumer I want personal information in as few places as possible," he said.

Opening multiple credit card accounts can have unintended consequences to a credit score as well. While maintaining multiple credit lines with timely payment history can benefit a credit score, making multiple requests to set up new lines of credit can hurt a score, Kley pointed out.

In addition, the types of credit matter. Jeff Blyskal, a banking and money specialist at Consumers' Union, recommends against taking out store brand credit cards rather than credit cards issued by banks. Because many store brand cards are issued by finance companies that issue more expensive commercial debt rather than relying on checking and savings accounts to fund the credit, they "don't score as well" on credit rating models, he said.

For most people, in addition to a debit card he recommends holding two major credit cards, one for backup if the primary card is blocked for some reason. Blyskal also steers consumers away from larger banks, citing a survey of Consumer Report readers in 2014 that found the highest customer satisfaction from customers of smaller banks and credit unions.

Another potential pitfall is losing track of accounts which become "unclaimed property." We're not talking inheritance from a Nigerian prince here but checking and savings accounts, brokerage accounts, safety deposit boxes or utility deposits that are held in each state. While personal finance software makes it easier for consumers to track multiple accounts, there are still tens of billions of dollars held across all 50 states in unclaimed property, according to the National Association of Unclaimed Property Administrators.

During fiscal year 2016, which ended June 30, the Minnesota Commerce Department's Unclaimed Property Program paid a total of $49.3 million to 30,412 recipients, record-high numbers and up more than 50 percent over the previous year in both dollars and claims. At the end of the year, the state was still holding $695 million in unclaimed property.

Perhaps the biggest question consumers have to ask is what sort of relationship do they want with their banks. Carlson's Kley recalls when many consumers would go to their local banker with any money question. The rise of mobile and online banking and the ease of opening accounts has accelerated a trend away from that trusting relationship to one that is more transactional, based on convenience and cost, he said.

Rick Gobell, president of Drake Bank in St. Paul and chairman of the Independent Community Bankers of Minnesota, said the Wells Fargo scandal gave banking "a black eye" that erodes trust between a bank and its customers. Not surprisingly, Gobell argues that the high-pressure sales culture that fueled the unauthorized account problems at Wells Fargo does not exist at smaller community banks that tend to know their customers.

Gobell echoes Kley's view of the changing landscape between banks and consumers. Multiple accounts held at different institutions has become "more and more prevalent" primarily because it has become so much easier for individuals to open accounts. "I don't think it's an issue that's going away," he concluded.

Brad Allen is a freelance journalist and former investor relations executive for companies including Imation Corp. and Cray Research. His e-mail is brad@bdallen.com.