Selling common property.

You won’t find much there.  What you are looking for may be in the Strata Schemes Freehold Development Act 1975 (see below) 

25 Transfer or lease of common property

 (1) A body corporate may, pursuant to a special resolution, execute a transfer or lease of common property other than common property the subject of a lease accepted or acquired by the body corporate under section 19 (2).

(1A) Subsection (1) does not authorise a transfer by the body corporate under a strata scheme that is part of a community scheme under the Community Land Development Act 1989 .

(2) A body corporate, pursuant to a special resolution, may, if not prevented by the terms of the lease, transfer a lease of common property accepted or acquired by the body corporate under section 19 (2) or grant, by way of sub-lease, a lease of its estate or interest in common propertythe subject of a lease so accepted or acquired.

(2A) A body corporate may, pursuant to a special resolution, execute a variation of any such lease or sublease pursuant to section 55A of the Real Property Act 1900 .

(3) A body corporate may, pursuant to a special resolution, accept a surrender of a lease, or, if otherwise empowered so to do, re-enter under a lease, granted under subsection (1) or (2).

(4) The Registrar-General shall register a dealing referred to in this section by making in the Register such recordings with respect to the dealing as he considers appropriate.