I prefer a roof rack over a trunk rack. And a Thule over a Yakima.
I've had 3 Thules, 1 Yakima, and 1 Saris Bones. Compared to the other trunk racks I've seen in use (friends'), the Bones is the best. Even though I never put more than 2 bikes on, I bought the 3-bike Bones since it had 4 arms instead of 3, for more stability. It was a pain to mount/remove from my trunk for every use, I'd have to be careful about scratching the trunk or bumper with either the bike or the strap buckles, and most importantly, I couldn't lock my bike to it. But it was fine as far as trunk racks go.
Thule vs. Yakima can resemble a Campy vs. Shimano or Grip Shift vs. RapidFire debate. They're both good. I found the Thule to be slightly easier to install and I really like the VeloVise (now V²) tray, which can also be used with Yakima bars. On the Yakima, I used to have the AnkleBiter clamp, which was stable enough to hold my 25-30 lb mountain bikes at speeds in excess of 90 mph. I'm currently using a manufacturer-specific Thule rack, which is the easiest of all since it just bolts directly to the roof of my car. Takes practically no time at all to install/remove.
A friend of mine used to have the Saris roof rack, and it was easy to install and was stable, but at the time there was no way to lock the bikes to the rack (short of using a long cable). I don't know if the newer ones have a lock function now. This same friend is now using a SportWorks hitch rack on his SUV, and it seems like an efficient way to go if you want to use a hitch.
You could always try to find a rack in good condition at a good price on eBay, and just put your bike in the trunk for any rides you do between this Friday and whenever the eBay transaction concludes. I'll actually be selling my spare Thule rack soon, but I haven't gotten around to it yet.