I bought a car with a salvage title from a backyard bodyshop guy and the car looked amazing. Brand new paint job and the interior was brand new too. It was the best deal I could find for the money I wanted to spend (under 4000). This was in SoCal and after driving it for three months, I didn't find anything wrong with it.
Upon closer inspection, I could tell that there was major damage to the car. The air filter box was cracked under the hood and when I looked at my car from the front, I could tell the body was slightly crooked. Also, I could tell a bunch of places were bondoed (by tapping around and listening for the plasticky sound)
After three months, I shipped the car with me to the East Coast and kept it there for the next 9 months. During those 9 months, the car totally fell apart on me. I discovered that the frame was rusted (underneath that brand new paint job). It had major electrical problems and the tranny was messed up. I didn't understand how there could be rust but found out that the car wasn't originally from SoCal because I found some papers linking it to a dealership somewhere in Utah (don't remember exactly if it was Utah but I remember it was a place that snows).
If I had to do it over again, I don't think I would get a car with a salvage title. If my next car is a used car, I would get one of those vehicle history checks. I don't know how good these records are but if its gonna be like 20 bucks, I think it would be worth it.