Subdividing in Canberra

Has anyone here had much experience with subdivisions in the ACT?

I am considering purchasing a block in an RZ2 zone which, if I read it correctly on ACTPLA's site, is subdividable if it is 800sqm+.

What would be the estimated ballpark cost to have this done with approvals etc? I am thinking of a battle-axe arrangement, keeping the existing house and building another at the back of the block.

I was also considering dual occ, but having the 2 houses on the same title would present selling (not that I'm planning to) issues down the track I would think.

Talk with ACTPLA first.

I recently spent about $5K all up to convert two existing cottages under a single title (1200sqm) to unit title- the equivalent of strata title.

Because it was already approved for dual occ I had no issues. Otherwise I would not have been able to split.

There is also a betterment tax, which sometimes can be substantial. Because my block already had two buildings that was not too big.
as Geoff said betterment tax is the killer. My understanding is though that it's only applicable if you strata title the two blocks which allows you to sell them separately down the track. Recommend to talk to ACTPLA