Inside Kim Kardashian & Kanye West's Old Bel-Air Mansion, It's for Sale Again

Kim Kardashian West and Kanye's old Bel-Air pad -- the one they transformed and sold for nearly $18 mil -- is back on the market ... and we've obtained never-before-seen pics in and around the palace.

TMZ broke the story, Kimye sold the 10,000 square foot home for $17.8 million back in November. It was scooped up by Ukranian billionaire Marina Acton, who also struck a friendship with Kim in the process.

The crib's full of marble floors, gold fixtures and a complete chef's kitchen. Doesn't look like Marina did much with the walls Kim and Kanye left her ... just a lot of white. And we're told asking price is a totally reasonable -- relatively speaking -- $18 million. The Altman brothers at Douglas Elliman Real Estate Co. will rep the sale.

Acton tells us she's still in love with the home, but is expecting a baby in a few months, so she needs more space ... 10,000 sq. feet more!

Marina -- who says she's having a girl -- tells us her parents plan to join her when she moves, and a new place in Miami or West Palm Beach with a guest house would be ideal.

As for a budget on her new place? Marina said what you'd expect from someone flipping 8-figure mansions ... "The sky is the limit."