What it's really like to get a $150,000 book advance, according to 'Bad With Money' author Gaby Dunn

Gaby Dunn, an author, actress and podcaster in Los Angeles, earned six figures last year. The majority of that came from the $150,000 advance she received for her second book, "Bad with Money: The Imperfect Art of Getting Your Financial Sh*t Together."

But although signing a six-figure book deal seems lucrative and exciting, the payment process is complicated, and authors don't end up pocketing nearly as much as you might think.

Here's what it's really like to earn a hefty book advance.

When she sold her first book, which she co-wrote with Allison Raskin, for another six-figure deal, Dunn was stunned by the amount she and Raskin were offered.

"The advance was a number that was unfathomable to me," she tells CNBC Make It. "I called my bank to be, like, 'Can my account hold this? Like, is that allowed?'"

But after splitting the total with Raskin and paying out a percentage to everyone who helped sell the book, Dunn estimates that she only took home around $30,000 before taxes. She pays taxes quarterly and, because she's not employed by a company that automatically withholds them for her, it's up to Dunn to put away enough to cover the amount she owes.

For "Bad With Money," Dunn earned a $150,000 advance and estimates that she spent around $50,000 of that to pay her manager and other members of her team. The amount that's left is then delivered in a series of installments.

She received a portion when she signed the deal, another when she turned the draft in, and a third when the book was published on January 1, 2019. She'll also receive another installment down the line.

"It sounds like a lot of money, but it's split up over, like, three years," she says.

Dunn also learned that a successful book can lead to a second deal, but that doesn't necessarily come with a higher paycheck. Although she and Raskin are writing a sequel to their co-authored book, "I Hate Everyone But You," they only earned a $75,000 advance this time around, which was divvied up between them and their team.

"Our first book got on The New York Times best-seller list, so you would think that our advance after that would be more," Dunn says. "But even though a book gets on the bestseller list, it doesn't mean it recoups its money."

Although Dunn says it's typical to earn a lower advance for a sequel, she says that "it was interesting because in my mind it was such a success."

Because she gets paid sporadically for her books, and because freelance work is unpredictable, Dunn's income can be irregular. That makes it difficult to budget and plan ahead.

"When I worked at a full-time job, you would get paid every week, but now it could be six months before anything goes into my income," she says.

And although Dunn is financially stable now, that wasn't always the case. "When I was in my 20s, I made almost no money. I was freelancing or I would take these really low-paying jobs, or I didn't have jobs," she says. "I realized it was a thing that no one was talking about and everyone just sort of pretended to be on the same level. And so I was embarrassed. I was ashamed.

"I would go through phases where I would have some money and then I would immediately spend it to make up for debts I had gotten into in the past."

Because she worked in entertainment, people often assumed that Dunn earned a lot. The reality of her financial situation made her feel isolated and alone. That eventually prompted her to start her podcast and begin talking openly about finances.

"I've just eliminated shame," she says. "It's a waste of time to be embarrassed. If I go into the bank and I just pussyfoot around about what's wrong, I'm not going to get the help that I need."

Update: CNBC Make It revised the income figure on April 3, 2019, after failing to confirm the previously published number.

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