Perhaps ask yourself why you want the Rav4? I did not know that reliability is lower for the Rav4. Yes, the mileage is not as good and it costs more than a Matrix. I test drove a 2010 matrix this past summer prior to buying a 2009 R4 V6 Sport. We obviously did not get to compare 4WD capabilities in snow. Very generally my impression is that if I were a young single person with an active life that the Matrix would be a good blend of style, mileage, affordability and features. Wanting more comfort now that I'm old and more solidity= safety with a child, we felt more comfortable in the Rav.
Any 2005 vehicle is going to be less reliable and require more maint than almost any 2011. I'd figure out the oldest vehicle you can get as cert preowned... and go from there. 2009 would be a better bet if you want it to be pretty trouble free for 5years. Personally I think you'll be happier overall with the newer matrix. It is a nice little car.
You should continue to research and see what year rav4 and matrix you should afford. If you know how much you have and how much your folks have to contribute you can do the math pretty easily. Look at Kelly Blue Book and NADA values. If I were you, I'd strongly consider Certified Pre Owned from a Toyota dealer. Look at the NADA values and kbb values for cpo. Decide on maximum miles you want on the new rig. Decide on trim package you want.
Then assume you can get a deal for around a grand under kbb or maybe two grand under nada. Then go out and look at what's on dealer lots. Check cars.com. Be willing to travel a good distance if you see what you want. Play them off against each other. You can make your deals over the phone too. If you see what you want but it's at a dealer 100 miles away, make a solid offer. If nada has the vehicle at 22,000...with that same mileage, and you are seeing similar vehicles going for 21,000...call the dealer up and offer them 19,500 and make sure you let them know you are pre-authorized for the loan value or that you will be paying cash( if you don't need to finance).
The warranty does not have to be serviced at the dealer you purchase at. You can get it warranteed locally. Don't let them dick around and try to gear the purchase price around monthly payments. If you really cannot make a deal happen at that price... then retreat and move your thinking to a vehicle one year older. Get your number in your head and down on paper. Know the Kbb and Nada cpo values for that year and mileage. If they try to steer you to another similar vehicle, but older, or higher mileage, or lower trim package... leave the place and go get coffee and pull out your smartphone, run the new vehicle and see want price would need to be to make it a great deal for you.
Also, stay away from the V6 Rav4. Although on paper EPA mileage is only 2 off from the 4 cylinder... in reality it's easy to do a LOT worse than that with the 6. Plus it's rather dangerously fast.
Week after Christmas is an awesome time to visit the dealer and GET THE DEAL YOU WANT. They're in there bored to tears drinking eggnog and trying to remember what a customer looks like, and in you walk with cash wanting to drive that blue 2010 matrix off the lot before 5:00. End of the month AND end of the year quotas to meet... you're probably going to be able to name your price and if you stick to your guns, get it. ALWAYS be ready to walk away however if things are going south. You have additional ammo if you've been watching the dealer's website and KNOW that this paticular 2010 matrix is dealer stock #2910387 (or whatever) and that it has been on their lot for over four weeks. After 3-4 weeks, dealers HAVE to get rid of cpo vehicles because Toyota insists that "stale " vehicles be gone... even if they have to move it to auction and lose money. Even though your deal may be WAY below NADA, they may still make out better by selling to you vs. selling at auction for three grand less... especially if all the work to get it to cpo condition has already been done.
Anyway, good luck. You're lucky to have parents that are helping you out.
2009 RAV4 Sport 4WD V6 SAP