Probably what some of us are still doing. Develop the technique and keep the $500 in your pocket.
I'd say the greatest time investment is waiting for the Con/Cem to start to set (15 min x 2).
Cutting the seam with a straight-edge, 30 sec x 2. Closing the seam, 2 min tops.
Granted there's some detailing and clean-up to be done and that's generally where the difference lies.
Spend the time on detailing and you can get close to perfect.
Try to not make the task more difficult than it needs to be.
It doesn't take expensive equipment to it right. Your technique does that.
Amen and twice on Sunday. I'm like you. I had the privilege of meeting Mr. D'Angelo and talked to him on the phone a few times after that. It's a shame his visit in this Industry was short and I certainly understand why he stopped. He had some great ideas.