We bought a light-weight camping pop-up trailer and now I have to modify my 2008 Outback to tow it. What do we need?  Yes, a towing trailer hitch (class 2, I think?), receiver, 2"ball, but what else?

Thanks for you help!

The trailer harness for the lights. 4 pin connector. You may or may not have the harness already installed that you can just plug into.