Here are photos showing my bike racks and hitch receiver (Curt hitch receiver 13509, Class III, 2"). I have both the Inno Rack Tire Hold (added optional 3rd bike holder) and the Saris Freedom (lighter option when I'm carrying 1 or 2 bikes). I prefer the platform tire hold hitch racks over the dual arm hitch racks (top tube mounted like the Yakima in previous post) since platforms are easier to load, are more stable/less sway, there is no load or contact with carbon bike frames, can hold 20-29" bikes, and there is no need for any top tube adapters. The InnoRack can fold down (with no bikes loaded) to allow the rear swing door to fully open; the unloaded Saris will allow the door to open 3/4 when the center post is folded down, and 1/3 open when single bike is mounted on far platform.
I think the roof mounted carriers are disasters waiting to happen. I've heard the sickening noise of my friend taking out his bike and overhead carrier entering a parking garage where we were meeting up for a ride, and damaging the roof of his Lexus in the process.
Another (and inexpensive way) to go is to carry the bikes inside the RAV4 and use fork mounts connected to a wood base and a velcro strap to hold things down. You can carry 2 bikes inside and still use the single 2nd row seat, or carry 4 bikes if you fold down both seats and add another pair of fork mounts on a base.
Costs (pre-tax):
Curt Hitch Receiver 13509: ~ $130 (http://www.amazon.com/Curt-Manufacturing-13509-Class-Receiver/dp/B001C6GQQ8), save yourself the $60 installation fee the shop charges (took them 5 min) and have a friend help you mount this hitch receiver using the the 4 bolts
InnoRack Tire Hold INH305: ~ $320-350 (http://www.autoanything.com, or http://www.RackNRoad.com shop in Costa Mesa if you're in SoCal area)
InnoRack 3rd tray INH306: ~ $130-150
Saris Freedom: ~$210-220 (Performance Bike, Amazon)
Fork mounts + wood + velcro: ~ $50-60
InnoRack INH305 + 306
Saris Freedom
Curt Hitch Receiver 13509
Inside Homemade Bike Rack