The reason why I never book on TaskRabbit or Thumbtack anymore is because there's legitimately an 80% chance that they don't show up. There's no penalty for not showing up or expressing higher availability and just choosing from it.
This means that every repair or home service that I consider is a simple question. Is this worth rebooking multiple times or will I just bite the bullet and try to do it myself.
I would be willing to pay around 1.5 - 2X more than I book for if I had some guarantee - financial or otherwise, that they would show up. Just the ability to construct a simple equation in my head - "is this repair worth $X" in my head without trying to manage the cost of a no-show would be huge and would have me checking the cost of much more small repairs.