The most obvious place to put the house is not always the right one. If there is only a small area of flat land, you'll be tempted to use it for the house. It probably should be saved for the arrival, parking, or garden.
Houses can be built on a slope, but it means a lot of grading and walls later when you try to get enough flat land for the areas you need around the house.
Is there one particular spot on the property that seems just right in every way? Have you picnicked there and found it idyllic? Have you spent long winter evenings planning a house there? Has it occured to you that if you build your house there the spot will be gone? Maybe that's where your garden should be.