off-plan
adverb UK uk/ˌɒfˈplæn/ us/ˌɑːfˈplæn/
以期房方式购入，以买楼花方式购入
If you buy a house, apartment, etc. off-plan, you buy it before it is built, when only the plans for it exist.
An estimated 85 per cent of UK investors bought properties in the area off-plan. 据估计，85% 的英国投资者在该地区购买房产时采用了买期房的方式。
The firm claimed to have sold hundreds of the 800 apartments off-plan.