It’s hard to say how many virtual financial advisors are out there because industry trackers aren’t keeping count. But more advisors are launching virtual-only practices and brick-and-mortar firms are also delivering more advice remotely to clients they may rarely or never see.

Virtual advisors range in age from baby boomers to millennials, said Michael Kitces, a partner and director of wealth management with Maryland-headquartered Pinnacle Advisory Group and co-founder of XY Planning Network. Virtual advisors span from larger firms (such as Vanguard Personal Advisor Services and Personal Capital) to solo firms (including XYPN members), he said.

Lower operating costs are one attraction. According to McKinsey & Co.’s 2015 report “The Virtual Financial Advisor: Delivering Personalized Financial Advice in the Digital Age,” a successful virtual model can deliver cost reductions of as much as 40% to 50%. The average advisory firm spends approximately 4% of its revenue on rent, said Kitces, so presumably that would be some of the cost savings.

“But that varies wildly by firm depending on size and location,” said Kitces. “And for many firms, it’s more about being able to serve clients anywhere, than cost savings of an office.”

Flexibility enticed Lazetta Rainey Braxton, an MBA and CFP, to adapt a virtual model in 2008 when she launched Financial Fountains, her fee-only comprehensive financial planning firm that serves mass-affluent clients and works on a retainer basis.

Braxton, now a New Yorker, didn’t have to stop and start her practice every time her family moved around the country for her husband’s career. Her home-based virtual practice also reduces her overhead, allows her to be more present for her daughter, makes it easy for her to continue to work with clients who’ve moved, and gives her more time for speaking and consulting engagements, she said.

A virtual practice might not work “if you need energy from the buzz of the office,” said Braxton, “but I’m not wired that way.”

Until two years ago, she rented office space that provided a mailing address, a receptionist and a place to meet with clients. She stopped because even local clients, busy with their own lives, liked the convenience of meeting virtually.

She now uses the Zoom platform for client videoconferences and works with an executive assistant who lives in Florida. When on-boarding clients, she walks them through the technology and teaches them how to link accounts, find documents and share screens.

“Even if clients don’t see me in person,” she said, “the relationships are still very personal.” Retirees are often comfortable communicating virtually because that’s how they already connect with their grandchildren, she added.

Reliable technology is a must in a virtual practice, said Braxton. An annual vendor stack audit helps her see how her technology is being used, how much it costs, whether it’s still relevant and cost effective, and if there are better ways to perform tasks.

Luis Rosa, a CFP and IRS enrolled agent, describes becoming a virtual advisor as “a happy accident.”

When he and his wife moved to Las Vegas several years ago for her to attend a university program, a handful of his wealth planning clients and 110 tax clients stuck with him. Later, more wealth planning clients trickled in from his former East Coast practice. He discovered that clients don’t mind the distance and that he enjoys working virtually.

“I’m no longer bound by zipcode,” said Rosa, founder of Build A Better Financial Future LLC, a virtual firm with clients in nine states. His clients are typically GenXers with $150,000 in investible assets plus 401(k) plan assets.

Rosa, a fee-only advisor, offers a variety of services and posts fees on his website. He thinks virtual practices with monthly fees resonate well with younger clients who need help budgeting, paying off student debt, buying a house, planning for a wedding or baby, and understanding 401(k) plans.

He calls clients on their birthdays, connects with them on Facebook to stay abreast of changes in their lives and sends them his newsletter twice a month. He recently began hosting the podcast “On My Way to Wealth.” He thinks contributing to mainstream media has given him more credibility with clients.

Rosa, a member of virtual study group with other FPA NexGen advisors, suggests that virtual advisors find other advisors with whom they can share best practices.

Even Jim Holtzman, a wealth advisor and shareholder at Legend Wealth Advisors, a Pittsburgh-headquartered RIA firm, estimates 25% to 35% of his clients are now virtual-only. Some moved out of state for retirement or for jobs. Others found Legend through the firm’s webcasts or just find it more convenient to meet virtually.

“Sometimes we laugh because the client around the corner is the one we never see,” he said.