I used about 15 10ft 2x4s, 3 one inch diameter 10ft PVC pipes, 2 sheets of plywood, a shit ton of 2.5 inch screws and 2 inch screws for the rail, and we used concrete for the foundation of the ramp part of it.
Mine costed about 100 bucks because my dad already had a lot of the materials from his company. Lowes and Home Depot will have everything you need. If you're parents or family have a construction company like mine, they may go to a builder supply and they generally sell things cheaper to long time buyers so you could get some deals on wood/ plywood.
 It took me like a week and a half but could be done in a day or two if you devote the whole day to it and you have everything you need to do it.
You could definitely find better instructions in that cult than I could give but if you wanna know how I did mine pm me or something.