This picture has been used (by myself) more times than I care to admit, so very sorry for the reposts to those who have seen it before...
This was very easy to do. Drive four (about 3ft long) pieces of rebar into the ground leaving about 2 feet exposed and slip the PVC over it. NO need to drive the PVC into the ground. If you angle the rebar, you will be able to create a tension in the posts that help support during high winds.
Cost for this one was -- about 7-8x PVC pipes at 8+ft long, 4x 3-way corners, and 2x "T's" and 4x 3-4ft lengths of rebar -- super cheap
Here is a smaller one, covering a 2'x2' raised bed
This one, I drilled the rebar straight up and down but in the smaller footing, creating this arc in the PVC. This has lasted for three years and running strong so far
Just some ideas beyond a standard hoop-house. I have both, and my hoop-house limits my plants when they're right next to the side walls and they get tall.
.