The power couple, who bought the £6.6million five-bedroom property last year, will not move in until July or August, around the same time that they will be tying the knot in Paris.
Perfectionist Kanye, 36, is said to be masterminding the changes in the house, which include building a new gym, home cinema, bowling alley, "top quality" recording studio, basketball court and glamorous dressing room, Life & Style magazine reports.
"It's frustrating for Kim," an insider told the publication, adding that the Yeezus rapper wasn't open to her ideas. "He's impossible to please and thinks nothing of changing direction midway and starting over."
The home improvements also include state-of-the-art kitchen appliances, including a Swarovski-encrusted fridge-freezer, and the finest furniture, including beds made from cashmere, virgin lamb's wool and Mongolian horse hair.
"Kanye is obsessed with every single aspect of this house," another insider said. "He says it's like a work of art and that there's no detail too small for him to be involved in."
Kim and Kanye, who are parents to seven-month-old daughter North, have been living with Kim's mother Kris Jenner in her Calabasas mansion while the renovations are being carried out.
Another big project on their mind will be planning their summer wedding. The engaged couple have decided on Paris, a city they often visit and which the queen of reality TV has called their "second home".
"We'll be getting married this summer, hopefully in Paris," Kim said, speaking on Jimmy Kimmel Live, adding that Kanye will "take care of the music and I'll take care of the seating chart."
"I know they think, or they say that the guy usually doesn't care and just shows up," she said. "Kanye really cares, he's really passionate about it so it makes my job so much easier. But I love it because he knows what he wants and I love him for that."
Previous reports had suggested that Kim and Kanye would marry in the Palace of Versailles, but Kim confirmed that the stylish couple were just taking a tour of the French landmark.