I've now installed 5 trailer hitches. The easiest was on my pick up truck - just bolted on. The hardest was probably on my BMW - had to remove the rear bumper. I had to drop the muffler to install the hitch on my wife's Prius, which was challenging but doable.
One trick I've leaned from doing this is that it is often helpful to scour car forums and YouTube for advice and tutorials to make it easier. For example, on my current Honda Passport, the OEM hitch comes with a new lower bumper fascia. The official instructions call for removing the entire rear fascia. But on one of the Passport forums, someone showed how they were able to remove the lower fascia with a stubby 10mm ratcheting box wrench. I bought the $8 wrench and was able to replace the lower bumper fascia and install the hitch in about 25 min.