In the case of a sale of a unit in which delivery of a public offering statement is required, a contract of sale may be executed unless otherwise prohibited by applicable law, but interest in that unit may not be conveyed until:

(1) The declaration and map that create the common interest community in which that unit is located are recorded pursuant to RCW 64.90.200(1) and 64.90.245(3); and

(2) In the case of a unit in a building containing that unit or a building comprising that unit, the unit is substantially completed and available for occupancy, and all structural components and mechanical systems of the building containing or comprising that unit are substantially completed, but a declarant or dealer and a purchaser may otherwise specifically agree in writing as to the extent to which the unit will not be substantially completed and available and to which any structural components and mechanical systems will not be substantially completed at the time of conveyance.