I haven't read all the posts above. I did notice the advice in post 6 is well worth following.
I offered input on this matter on many an occasions. Here are some, I don't have time to dig them all up for you. I'm sorry.
- this post addresses strategy in the car buying process.
- this post was in response to a question about buying a new car, but many of it's concepts are applicable to that of buying used cars as well, especially the concept of floor plan, which is especially important.
Lastly, I sent TrentOSU (another member) one or two very involved emails regarding the buying process. He recently bought a car similar to the one you are considering and in a similar price range I believe. He may still have the emails I sent him and if so, ask him for them. Tell him I put you on to him.
All the best.