Turn key

This commonly means a contract where you are delivered a completed new house and land. Generally you enter into this contract early on in the build and sometimes the land parcel might not be fully divided yet.

The advantage can be in a busy property market, if property prices continue to move up during the build, you have an increase in wealth on the day of taking possession.(without paying any interest during the build time)

Risks which need to be mitigated may arise. Such as delays in the completion or worse financial trouble for the developer. Your lawyer should be consulted before going unconditional, to protect your deposit.

Land and Build

Buying a piece of land can give you a bit more control, however you do need to budget for paying interest while you complete a build. Banks do offer finance for construction, currently 90% of the costs.

Also building can mean that the design can suit your own needs and taste.