International company, WorldMark South Pacific Club, will take over the Sebastopol property at the end of July, converting it from a wedding and conference centre into an exclusive members' holiday resort.

The purchase price was not disclosed.

The redevelopment will involve converting some of the existing rooms into apartments.

The complex _ presently known as Blythewood Grange Country Retreat _ will be rebranded WorldMark Ballarat and will be absorbed into the group's 50-strong portfolio of international resorts.

Staff at Blythewood were notified of the sale on Thursday and it is anticipated that most will be re-employed by the new owner.

Grange Group managing director William Balcam said the sale followed two months of negotiations and was eventually signed off when he was satisfied staff and patrons would be looked after.

Under the agreement, all wedding and function bookings will be honoured. Conferences will be hosted at Blythewood until the ownership change-over, after which time they will be accommodated at one of the Grange Groups' four remaining conference centres.

"All of the staff will have the opportunity of applying (for positions). We've got excellent staff, and I'd have no doubts that people (the new owners) would pick them up .. and they've basically indicated that (they would)," Mr Balcam said.

"I expect most, if not all to be re-employed."

WorldMark's resort development director Chuck Stone said the property was an attractive buy for the group.

"WorldMark South Pacific was attracted to the property owing to its proximity to Melbourne, the historic nature and character of the structures, the existing amenities, the lake and gardens, and the community and history of Ballarat.

"Our intent is to leave as much of the character as possible in the interior of the buildings, as this is the appeal of staying at the resort."

The Blythewood estate includes 22ha of grounds, an indoor swimming pool, spa, sauna, conference facilities for up to 180 people and 57 ensuite rooms.