"Christina is looking forward to working on new projects, and their own solo projects. It was time to be done," a source close to Haack tells ET. "The series is ending with great ratings. She is starting to film Christina on the Coast next week."
Another source tells ET that El Moussa and Haack have joint custody of their two kids, 11-year-old Taylor and 6-year-old Brayden, and work hard to co-parent successfully. "They communicate for the kids," says the source. "Off set, they aren’t really friends."
On the Flip or Flop series finale, the former couple take on a "monster" pool that's better described as "a sink hole," and the pressure of such a job leads El Moussa to walk off camera.
El Moussa, Haack and their trusted contractor, Jeff Lawrence, are all taken aback by the massive work in the backyard that features a gargantuan pool that clearly needs a ton of work and will prove to be expensive. In a sneak peek of the final episode, dubbed "Spanish Lessons," El Moussa initially guesses that fixing the pool alone will be $10,000 because it'll need to be re-plastered and re-tiled.
Lawrence guesses that, because "this thing's a monster," it'll be more in the $13,000 ballpark range. Upon further inspection, El Moussa and Haack also notice cracks, prompting El Moussa to say, "This is not good." Haack responds, "It's like a sink hole."
That being said, Haack remains optimistic about the challenge ahead.
“But look on the bright side," she says before El Moussa chimes in that fixing the pool will increase the home's value. "Yes, that too but we also get to do a fun design like that cool gloss tile or, because it's Spanish, maybe a cool clay tile."
El Moussa shoots down Haack's creative suggestions while walking away from the on-camera interview, leaving Haack alone, smiling and telling the camera, "What about a water slide? Oh, I know, a waterfall!"
El Moussa and Haack in previous flips have tried to pull off the elaborate Spanish design while keeping costs at a minimum. It's proven to be difficult and costly, but they hope past experiences have taught them better as they once again attempt to master the complicated style.
The Flip or Flop series finale sneak peek comes less than a week after it was announced that the show was ending after 10 seasons. The successful HGTV series -- which has spawned several other shows -- premiered in 2013, and during its run, fans got to witness the pair reach new heights as professional flippers and young parents. But the cameras also kept rolling after they experienced hardship too -- from their very public divorce in 2018 to El Moussa battling cancer. They've since moved on to new relationships.
“More than 90 million viewers have watched the popular series since its premiere in 2013. We look forward to seeing more of Tarek and Christina's real life, real estate and renovation adventures in upcoming episodes of their solo series Flipping 101 with Tarek El Moussa and Christina on the Coast," read a statement from the network.
A source told also ET at the time, "Christina and Tarek felt ready to move on from Flip or Flop. They both have a lot going on in their own careers and personal lives, and the timing felt right. They have a stable co-parenting relationship, but working together so closely was sometimes a lot."
El Moussa and Haack took to their Instagram accounts to confirm the news that their show was ending. El Moussa said the series ending was "bittersweet," but the writing had been on the wall for some time.
"You guys have been with us through it all -- you watched me beat cancer, you’ve watched the babies grow up into the most amazing little humans, and everything in between. But I’m not going anywhere and I can promise that you are going to love what comes next!" he said. "I couldn’t be more grateful for the last 10 years with Flip or Flop. The support from our fans, the network and the wild ride that it’s been has been incredible. Even though the Flip or Flop chapter is coming to a close, another exciting one is soon starting."
The Flip or Flop series finale airs Thursday at 8 p.m. ET/PT on HGTV.