I use a 1UPUSA bike carrier in the US and here in the UK. I use a double one but you can get at least three on there. They are insanely strong and easy to use. Each bike takes 20 seconds to pop in and secure. http://www.1upusa.com/product-quikrackblack.html
They are stunningly well engineered, better than any US engineering I have ever seen. I get complementary comments wherever I go. In the UK I fit it to my wife's old Prius and have happily gone to the south of France with them on the back. They do need a 1.25 or 2" hitch receiver. I get the excellent Curt ones from eBay.
On my Denver based one I changed one of the bays for a wider tyre for my fatbike.