I have heard of people like that, he may have no intention of doing
the work and never did. 50% down is an amount that leaves me suspicious
of his intent. Was he the cheapest and that is why you signed. If you
paid by credit card you can dispute the charges, but you probably paid
by check and it is to late to stop payment. Go to your local courthouse
and see if he has other cases against him, talk to you city lisencing
and see if he ever had a lisence and if he has one now. You may be out
the 5000 and need to go to court to "try" to collect. Do you know where
he lives, see if he owns or rents. You have a contract now but get him
to sign another one ane get proof of insurance-call the insurance co
your self and see if he is on the policy. Get a completion date.

wwwfreeadvise.com is a legal site that will help.

Your local DA will have free advise for you and on him if he is a crook.

Is his name B Henderson?

If he signs a new contract get a completion date, demand it is started
now, see what he says. Get proof of insurance then start checking hm
out. And never give 50 % down or any money till the job starts-next
time. Maybe he is honest but ive been ripped of by cons so I would be
worried.