Britney Spears' old digs -- the home that served as the backdrop when the singer went into free fall, shaved her head and ended up being involuntarily committed -- is back on the market, and anyone who still has millions of bucks can now get it for a steal. The pop singer's former Beverly Hills mansion -- where she lived after her divorce from Kevin Federline until 2012 -- is up for grabs for $6.8 million ... a pretty significant reduction from $9 mil when it was put up for sale in 2018.