March 31 (Reuters) - Australia's Domain Holdings

said on Monday it has granted CoStar ( CSGP ) exclusive

due diligence access for the U.S. property data group's revised

buyout proposal which values the real estate classifieds firm at

A$2.80 billion ($1.76 billion).

CoStar ( CSGP ) sweetened its offer to A$4.43 per share on a "best

and final" basis last week, a 5.5% premium to its initial

proposal of A$4.20.

CoStar ( CSGP ) will be granted access to a virtual data room,

Domain said in a statement, adding the exclusivity period will

expire in four weeks unless extended by a further two weeks.

The target company confirms the intentions of its board

members to unanimously recommend voting in favour of the

proposal.

($1 = 1.5918 Australian dollars)