You can do it yourself if you don't want to pay for it. Its a drop-in kit. You literally just strip the entire frame, swap out the sear, hammer, and trigger, and reassemble. It took me about an hour to do, tops.
If you can field strip your gun and have mild mechanical ability enough to pull it apart and put it back together, you can do the work. No machining, polishing, or modification was required in any way.
Not saying you "shouldn't" pay someone to do it for you, just saying its not as daunting a task as it might seem.