It is significantly easier to get 'Wreckage' Skills as opposed to 'Barrel Roll' Skills so this will only focus on the 'Wreckage' Skills.
Heading back to my favorite spot to get this challenge done. Head to fields to the right/east of the Yarra Valley Horizon Festival. I designate my spot at the beginning of the video.
Any D-class car should work, I personally used the 1971 Nissan Skyline 2000 GT-R, upgraded to all-wheel drive and to the the maximum you can get in D-class, 500.
For reference quickly, um, 'wrecking' things is how to get a 'Wreckage' skill. Just get 20 of them per the challenge description and it will pop.
When driving around through the fields you should see the various 'Wreckage' skills popping up at the top of the screen.
As shown this only takes around 2 minutes to do. You may not necessarily need to bank the skill chain as with previous challenges.