I am a contractor and had been on that site previously. I had a bad experience so I quit. I gave it 2 years and had hoped that they had stopped the fraudulent billing that forced me off the first time.
They did not.
They immediately charge for a lead when it is sent. The problem is that some of the leads are created by Thumbtack in order to drives sales. The phone numbers and emails are not legitimate and no one responds. I was notified of a lead and I called immediately. Within 10 seconds. My lead stated that I was the only contractor that the customer contacted. As I called I watched my screen and the lead changed to job filled. Impossible! I did not fill it. I contacted Thumbtack to get a refund and they refused of course. They did that again that same day. I was billed over $100 for 2 ficticious leads. I complained vigorously and they closed my account and kept my money.
If an attorney wants to file a class action suit please contact me.