Actress Denise Richards has placed her 5,651-square-foot mansion in Hidden Hills, Calif. on the market for $4,250,000.  Our pals over at the Real Estalker broke the story yesterday of the clearly peripatetic Richards' latest real-estate move, which involves turning around and trying to sell her current house, at 23726 Long Valley Road in Hidden Hills, just a year or so after she purchased it on June 29, 2007 for $4,395,000 through her Strudel Trust, according to public records. The house at 23726 Long Valley Road came on the market on Tuesday. We have chronicled Richards' many real estate moves many times in the past. The simple thing to know, however, is that if her current house sells for its current listing price, Richards would lose money on her second consecutive real estate transaction! That is because Richards sold her last house, which is just across the street at 23703 Long Valley Road in Hidden Hills, in October 2007 for $3,800,000 after having bought it in May 2006 through her Lucy Trust for $4,000,000, according to public records. Built in 1991, Richards' house at 23726 Long Valley Road has five baths, custom ceilings, dark wood floors, and a chef's kitchen with top-of-the-line appliances, marble counters, custom cabinetry and a breakfast room, according to public records and listing information. The house also has a gym, an upstairs office, and a master suite that has an island spa tub, a steam shower, Carrera marble counters and a brick fireplace, according to listing information. Check out an online listing sheet for Richards' house at 23726 Long Valley Road -- complete with photos. There's no word yet on where Richards is headed. We'll of course keep you posted as we learn more.