Contractor billed me for a estimate

[Christopher Morin]

We solicited a bid on a rehab from a new contractor, which included a walkthrough with him.  He provided a 19k estimate, which was much than our other bid (of 9k).  I told him I'd get back to him.

4 days later, he sent me an invoice for 4 hours worth of work, total of $200!  What in the world!  I've solicited of bids from dozens of contractors, without even the slightest hint of being billed for an estimate.  I think I just got a guy who realized he wasn't going to get the job and wanted to squeeze extra money from me.

I want to just blow him off, and make it a point to never use him again.  What would you do here?  Any legal safeguards I need to take?