Ok Petchat people, I have developed my own agility kit! I am so so excited. Would love your feedback!

I used 1½" pipe, this is the materials list and some measurements:
NOTE: these measurements are not exact.

2 feet wide.
4 feet wide.
8 feet wide and < 20 feet of pipe.
4 x 5" feet from the feet wide to spacer T.
4 x 9.5" feet from the spacer to the uprights.
2 x 6" risers for the lower PVC pivot bar, this give a 12" high teeter with a 2" plank.
2 x 9" risers from the lower bar up to the double feet wide.
4 x 2' 45 degree stabilisers.
3 X 14.5" for the spacers and lower pivot bar. I might shorten these once I decide how to attach the plank.

I guess the imperfections don't show in the pictures *lol*
This took the longest to put together so far, partly because I decided to use machine bolt and nuts (needing pre drilling) instead of self drilling screws. Didn't want any sharp points sticking out.

Material list:
2 12' lengths of 1.25" 6061-T6 Aluminum angle.
1 4' x 8' of ½" 4 ply plywood, I figured I'd try with this thickness first and it seems to work OK.
About 30 1" screws and bolts.

3 7½" long pieces of treated 4x2 lumber. One for each end (to keep feet from being skewered by the aluminum) and one as a support for the pivot point.
Another 12 wood screws, to secure the treated lumber to the aluminum.

Since I had to use two pieces of plywood, one 8' and one 4', I also have a 7½" piece of 1x4 under the joint. It's is secured with another 4 2" bolts with nuts through the plywood.

1 ½" galvanized rod, approx. 20" (sold in 3' sections usually).
2 ½" plastic/zinc push nuts.
2 ½" two hole straps.

2 cans of multi purpose spray paint, one of them yellow.
Some sand.

Used a measuring tape, jig saw, a drill and a hacksaw (for the metal).

Total cost for the plank ended up around £70 (including the extra material I will be able to use for other stuff later) 40 of that was the aluminum... Getting a normal 2x2x12' would have been a lot faster and cheaper, but I feel like doing it this way this was worth it.

I think I will add two short pieces of PVC pipe over the rod at the sides of the plank to keep it centered. And I might also make a shallow groove in the treated lumber that now rests against the pivot rod, so the rod comes in contact with the aluminum as well as the lumber.

It's our front yard Sandy, the shade you see by the teeter is cast by the garage. And the pinkish red thing you see at the right side of the second picture is Caden's lady bug sandbox lid. Tristan wanted me to point that out.

Material List:

Six 2x4, 12 foot long
Two 4x8 sheets of plywood. I went with 11/32" exterior plywood and it felt very flimsy so I added three 8 foot lengths of 2x3 to the frames.
100 1½" wood screws, for attaching the plywood to the frame and for the hinges
100 2½" wood screws, for framing (you can get away with 75 if you skip the 2x3s in the frame)
Some hinges for the top of the A-frame and a long rod to replace the hinge pins with. I'm not all that happy with the hinges right now, they're incredibly hard to line up, I'll see if I can figure out how to adjust it.
Screw eye and screw hook and chain.
Paint and sand.

Tools:
Power drill/screwdriver,
Circular saw
Snap line (to mark the framing on the plywood)
Ruler/level/something longish and straight/measuring tape

The cost for the lumber ended up being £20 for the 2x4s another $5 for the 2x3s and £36 for the plywood.
I got hardware in too many different places since I got the wrong length of screws, I think it ended up being about £15 for screws and maybe £10 for hinges, metal rod, hooks. I haven't got a chain yet, figured I'd measure how long it needed to be. The paint was £21 for a gallon of the yellow, I had blue exterior paint already. And I stole sand out of the boys' sandbox.

So this A-frame cost me a little more, but not much more, than £100. I'd definitely say it's worth building one if you compare that to how much it'd be to buy one.

JUMP:
Jump with a fixed lower bar for stability and an adjustable upper bar in jump cups. Jump height can be set between 8” and 32” (at least, I'm guesstimating).
You can easily build this jump to be up to code by adjusting the height measurements of the uprights (they’re a couple of inches too short in this version) and lower the fixed bar.

17 feet of pipe and 5 Ts

BASE
4 x 1' feet
2 x 6" lower bar upright
2 Ts for feet
2 x 24" uprights

BARS
2 x 4'
3 Ts 2 for the fixed lower bar and 1 split T for upper bar jump cups.

I’ve used ¾” PVC pipe and ¾” fittings
A hack saw with small teeth
Measuring tape
Pencil
Drain pipe and Duct tape for the tire
Sand paper (for those sharp edges, especially the jump cups)
End caps and I plan to get some tape to pretty everything up.