Only a fool would consider it like that.
You could do like this. Demand 1% down payment and use half to hire an inmate with a short time left in prison to start a riot and kill whom ever you want for you. All of your contact with your hired killer should be through the internet from a number of cyber cafes and always wear a disguise to inclue a hat and wig and leave no prints or DNA behind and talk as little as possible always with an accent. Do not even dress as you normally would and get rid of everything once the hit is made. Be sure there is no trace of any of the dedguise left behind and by all the items in several thrift stores one item at a time and never charge anything. And the little talking DNA rules apply every time all the time.
Once complete do not change your actions or spending habits in any way and make sure the money other than the down payment is in an offshore account or payed in unmarked bills. Make arangements to have the prison murderer report in some way to you when he gets out and have him kill who even hired you if that person can identify you. Then quietly move away and live the good life in a low key manner.

I kind of laughed out loud at your last sentence. Your answer is beautiful. I love the attention to detail. I'm supposing you would have to pay off the prison inmate quite a bit so that he wouldn't be a liability in the future. But, would be worth it, so long as he doesn't get greedy. Then you may have another situation to deal with, and unless you want to tie yourself to that crime, you'd need to find another associate.
Thank you for this! I posted this on a couple spots and nobody answered lol.

Thank you seren21. I enjoy writing fiction I wrote a whole off season episode of Psych for fun. But you have to have seen the season finale "An evening with Mr. Yang", for it to make sense at all. It can be seen at: link
In conclusion to your question.
When it comes to the inmate murderer he would have received plenty of money from the two jobs to keep him quiet and there's little chance he could blackmail you because you covered your tracks and can't be tied to the crimes. For him to talk he implicates himself and since he's been in the big house he won't want to go back. Besides you're care would keep him from knowing who you really are. Remember you learned how to hide in plain sight.
Once he's paid off you become yourself and you're gone.

To whom it may concern in law enforcement, I wrote all this using years of experience as a writer not as a crook. lol.