Based on this plan, the hard landscaping can be factored in early on by using the digger when it is on site, (for, say, the foundations), to create a solid base for hard landscaping.
This usually involves a layer of hardcore, chippings then sand, bedded down with a whacker. If there is drainage to go in, have the pipes laid for it, also any rainwater harvesting solutions for the garden. You may also need ducts for an electricity supply to external lighting, powered gates, or the sewage treatment package plant.
The levels will be worked out with the groundwork contractor. You will be glad to have this done when the time comes to actually invest in that patio or driveway project.
Having a clear plan to work to will also mean you can start planting trees (and other soft landscaping) at the very beginning of the project and have them semi mature by the time you move in. Trees are very costly when bought mature from the garden centre.
Planting during the dormant season will also allow you to buy bare-root plants (cheaper) instead of root-balled or container grown plants (dearer). Just make sure that trees and hedges, including existing ones, are properly protected.
Although getting the hard landscaping done along with the rest of the project is important, it is often better to spend a year getting to know your site really well before siting other features such as seating, decking, flower and shrub beds, vegetable patch, barbecue, and even the clothes line.