Do you have nice bikes?
Do you want to protect your bikes and your 5 from damage?
Are you ok with spending waaaay too much on it? 
Get a hitch and put one of these bad boys on:
This is a Sportworks Quick-load rack. They are the ones you see on the fronts of buses in a lot of places, and for good reason. They're very easy to get bikes on and off of, they'll accommodate almost any size or type of bike, and they don't damage your bike, as they only hold onto the front wheel, contacting it at the tire.
Sportworks no longer makes these for the retail market, and sold the design to Thule, which is actually kind of a good thing, 'cause it's easier to find a Thule dealer than it was to find a Sportworks dealer.
I bought mine when I worked a shop that sold them, so I didn't pay much. If
you don't work at a bike shop, and I'm guessing you don't by the fact that you asked us on here what rack to get, you'll end up paying $369 for one. It's totally worth it.
Here's the link to the Thule page with the info on their version.