My dream(Preferably a VW Passat

Even with a salvage title it will likely be hard to find a quick 2007 or newer car with under 70,000 miles for under $4,000. Have you found any?

You're beyond my area of experience.

Unless you've worked at a body shop/mechanics shop and know exactly what you're getting into I think you're tempting fate looking for a salvage vehicle. You're dealing with folks who are pros at hiding automotive problems; vehicles may have sat for a while, and you'll be buying as-is (I'm assuming?). I'd try to find a test-drivable vehicle off Craigslist or someplace like that from a private seller (the person who has been driving it; not a car flipper); have a mechanic check it; pay less than kbb.

Also, if you're OK with an Accord or TSX, I'd go with one of those over a Passat because they'll be cheaper to maintain, even though you will have to choose between older/higher milage.

Try looking around at some of the local repair shops that specialize in German cars. Some people bring in their cars and don't want to swallow repair costs for some things; the timing chain on the V6 comes to mind, something that doesn't happen until higher-mileage, but it can cost a pretty penny... Find the 3.6 V6 for the B6 Passat if you can, they're realibe and fun engines. The 2.0Ts are good too (have in in my GTI, and with regular maintenance and lots of care, they run fantastic), but require vigilance and religious maintenance... If you cant find something newer, I'd suggest a B5/B5.5 Passat ('99-2005) with the 2.8L V6. Smooth as butter and wonderful on the highway. Just try to find one that's had a regular timing belt change interval (80k miles) and has been fed full synthetic oil. Although even the worst maintained 2.8Ls can be brought back to life. As far as maintenance costs, if you're willing to do the preventative stuff yourself (oil changes, air filter, ect...) They're not bad. German cars need a steady diet of full-synthetic oils. I'd recommend Total/Elf or a Euro-brand oil, just because that's what they were intended to be run on.