In this segment of Motley Fool Answers, Alison Southwick and Robert Brokamp, along with Motley Fool Wealth Management's Sean Gates and Joe Perna, consider the appropriate investment vehicles for a 20-something who (well done, John!) is already putting a fair share into his 401(k) and routing some to a brokerage account as well.

The answer rides on one word: flexibility.

A full transcript follows the video.

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This podcast was recorded on Sept. 6, 2016.

Alison Southwick: John B. writes: "A friend recently mentioned that it doesn't make sense for people our age, in our late 20s... " Yes, John, that is our age, should anyone ask. I am in my late 20s. "... to be investing in a personal brokerage account if not maxing out a 401(k)." He continues: "I contribute 11% to my 401(k) with an 8% employer match. I also contribute biweekly payments to some index funds in a side brokerage account. Does it make sense to bump up my 401(k) contribution and eliminate my brokerage contributions?" Joe, this one's going to you.

Joe Perna: Yes. I would say [good for] John B. for saving diligently into the 401(k). It's good to get started early, so late 20s I would say, is starting fairly early.

Southwick: Yeah, that's good.

Robert Brokamp: That's pretty good.

Perna: And saving 19% will mean taking into account the employer match. That's pretty hefty. That's a good chunk to be putting toward the retirement plan. When thinking about saving into a 401(k) in the taxable account, I like the idea of having a taxable account due to the flexibility that you have.

That flexibility is huge when you're thinking about down payments for a house. When you're thinking about wedding costs if you're not married yet, or wedding rings, or automobile purchases. All of those things. Cost funds -- you need to be using money. When it's tied up in retirement accounts, you can't access those funds as easily.

So those taxable accounts, I think, are great. To me, the flexibility is fantastic, and I would say 19% is a good amount to be putting toward retirement. Additional flexibility is fantastic. I think there's not a problem there, and I would disagree with your friend. Maybe defriend him on Facebook.

Southwick: Oh, ho, ho.

Perna: Maybe not that far. But I think you're doing a great job, John B.

Southwick: So the next time a friend recently mentions that, then he can say, "No! I enjoy the flexibility that my taxable accounts give me because I plan on getting married and doing all these wonderful things with my life."

Perna: That's right. Stay out of my business.

Southwick: What do you know about me? You don't know me, friend!

Gates: The next time he talks to people, he won't have anyone to go to, because he will have alienated all of his friends.

Southwick: Who were just trying to help. Oh, man.