Have you thought about welded wire? You can buy 100 ft. roll at lowes for about 50-60 dollars. That would be the 2×4 holes that do not allow anything thru it.
You would then also have to buy either fence post’s or 4×4 to put in the ground. I am not sure how fancy you want this yard but the welded wire works great on my Labradors when they do not climb over:( Blessings, Theresa In Fl,