Thumbtack seems like a good idea and might work for some professionals like housecleaning or pet sitting where the service is straight forward and offered in a 30 mile radius.
But for people like me who work online, the platform does not work as promised. It is too easy for customers to use the service without being qualified in any way, primarily because it is free.
I found people generating requests fall into these categories:users online in the middle of the night when they are high or drunk; minors; competitors doing market research; individuals without any means of making payment i.e. they do not have access to PayPal or a credit card to pay for services (two actually asked me to do a marketing plan for free or "$10", one offered to mail me a check); tourists, meaning they submit requests they don't intend to review or follow-through on hiring.
As a marketing consultant and coach I do not recommend it for anything Thumbtack promises, specifically--building your list, generating social media activity, or finding leads.
I invested two weeks answering quotes without any payback. My profile has a 5 star rating, six reviews, and I bid under the average rate for my profession.
Here is my data.
Quotes Submitted: 34
Quotes Viewed: 18
Requests Identified as Competitors: 4 (this could be higher but I didn't want to waste more time investigating)
Requests from Minors: 2
Requests from People without Ability to Pay: 6
Hired but never paid: 1
Hired and paid: 0
It might work if Thumbtack required prospects to provide more information, such as to show they have the means to hire someone and pay them by PayPal or a credit card. Another data point needs to be the industry of the business for which they want a marketing.
There is no way a professional can qualify the leads beyond number of employees. For example, I received one request to write a plan for a 19 yo with a part-time job in retail who wants to open a hair salon and another to prepare a marketing strategy for doctor opening a chain of franchise locations. But you can't tell one from the other until after you have paid for the lead and then, only if the prospect communicates with you and does so honestly.
I believe most of the customers in my categories would disappear if Tack required credit cards and business description beyond # of employees. I strongly suspect the majority of the leads I paid for were fake.
Reviewer is in unhappy mood. This person stated that there is a room for improvement of cost and lack of good leads and does not qualify vendors. Please immediately contact the author of this review to discuss not as described of thumbtack leads and associated monetary loss in the amount of $380. Thumbtack needs to offer any options to resolve the issue according to poster's claims.