Sources close to the couple tell TMZ ... she plunked down $11.8 million for the mansion in Calabasas. The 11,650 sq. foot home is actually pretty close to where Kevin Federline lives with their 2 sons, Sean and Jayden.
According to property records, "Million Dollar Listing Los Angeles" stars Joshand Matt Altman of Douglas Elliman and Todd Bernstein of Coldwell Banker Residential Brokerage handled the listing and sale, but had no comment.
As for how K-Fed feels about the move -- a source tells us, "Kevin was surprised that of all the neighborhoods she can afford to move to she chose his. As long as his peace and tranquility aren't invaded as a result, more power to her."