I'll assume that your truck is within specs and can safely tow the trailer you want. I hope that you did the research YOURSELF and are NOT relying on a RV salesman for information. Things like total tow weight (wet, not dry), tongue weight, available payload are important things to know and double check before you buy. That being said, if you are reasonably handy you can install most of the stuff yourself.
I installed a tow hitch on my old SUV and my sisters minivan. I installed a Curt hitch both times. Chances are that there is a hitch that bolts straight to your vehicle. You can buy one online for a couple hundred and install it yourself or with a friend. Its usually a matter of holding it up, lining up the holes and installing bolts to a set torque. I think my hitch was about $250, my sisters was around the same. Figure a shop will upcharge the hitch and bang you for a couple hours labor... you can save several hundred dollars yourself.
Installing the wiring for the brake controller can be a little more involved. If your vehicle isn't already prewired for it, it might make sense to pay a pro to install that.
Weight distribution hitches are pretty easy to install yourself, so long as you have a tape measure, flat parking lot to take measurements, simple hand tools and a couple hours time. You can easily save a couple hundred doing this yourself.
