There are different types of roofs with different designs that could meet your budget.
The first thing you should do is calculate the square footage of your roof, this is the surface of the roof itself, not the square footage of the living space of your house. Every roof footage is different because because every house has a different roof slope. But it will usually be 110 to 130 percent of the living space of the top floor.
Next you need to decide what type pf roofing material you want to use. You decide this material with your budget. Asphalt shingles are the least expensive, and upscale houses sometimes have wood or slate roofing. You should go to several different home centers and compare roofing materials and prices.
Asphalt shingles are generally graded by the length of the guarantee that is offered by the manufacturer which is normally 20 to 50 years. The higher end asphalt shingles have a longer guarantee and a heavier more dimensional appearance. Wood and slate roofing have a smaller range of choices. If you are considering getting a slate roof, you will need to choose between manufactured and natural slate and select a color.
You should consult your roofing contractor before you order any material. Your roofing contractor should have experience with the material that you have chosen and that you are familiar with the installation costs. The cost could vary with different materials.
After that is settled you order the amount of roofing that is required to get the job done.
Some things you should know about roofing your home: Roofing is generally measured by the "square," which is equal to 100 square feet of coverage; Low-end asphalt shingles are generally very flat in appearance and have guarantees of approximately 20 years. High-end asphalt shingles have guarantees of 40 years or more and are much thicker and more dimensional in appearance. Expect to spend $40 to $100 per square for asphalt roofing; There is little variation in wood shingles beyond the choice to stain them a color. Wood shingles require significant ongoing maintenance - a serious consideration for home owners contemplating this selection. Wood roofing material generally costs in excess of $100 per square; Slate roofing is very expensive, with material costs generally starting at $200 per square for manufactured products. Natural slate is even more expensive.