Australia's REA falls on peer buyout, dour quarterly earnings

** Shares of digital advertising co REA Group REA.AX slips as much as 4.2% to A$239.5, their biggest intraday pct loss since April 7

** Peer Domain DHG.AX says U.S. listed CoStar CSGP.O would acquire the firm for A$3 billion

** Citi says REA's 'wait and see' approach to the Domain deal could cause minor consensus earnings downgrades

** REA's 12% Q3 revenue jump was driven mainly by a 15% price increase - Morningstar

** Morningstar says raising prices at double-digit rates could face regulatory scrutiny

** Citi maintains 'Buy' at PT A$275; Morningstar ups PT by 2% to A$130

** Stock last down 1.1%, trims YTD gains to 5.4%