Some of the information above is incorrect. Salvage Title does not always mean totaled- as in wrecked. Many states have variations of "branded" titles such as salvage or rebuilt. The problem is that these titles are not always indicative of why the car has received said title... Sometimes there is flood damage, sometimes there is a wreck, sometimes there is a theft recovery (if they've stolen the air bags and leather interior, etc... It's usually too expensive to repair or replace in the minds (ie: they have to spend ANY money) of the insurance companies so they "total" the car and it gets branded with a "salvage title" - even though nothing is wrong with it - besides the missing parts.
That being said, a branded title car is not one to be afraid of. You must simply take your time, inspect and ask questions. A branded title car is generally worth about 50% of a like-kind make and model... Example: Mercedes Benz that sells used for $25k... Then you have one that was stolen - missing seats, a bent rim and missing air bags... This has branded title but you can buy for $10k and replace the missing stuff for a few grand off of CL or ebay, etc... Now you have a $25k looking car for half the price.... I know many people who prefer to buy cars this way as you can have your cake and eat it too... Of course it won't be worth as much when and if you sell and probably a little harder to sell due to the stigma but still there are some great deals to be had.
As for the Prius--- Those cars are computers on wheels... It is likely that it would need to go to a Toyota shop as they'd have the expensive diagnostic tools and training. I'd avoid any car that I could not work on myself... (Since I do my own work, I can work on most cars- Prius is one I avoid- don't like to be at the mercy of others- especially a stealership)
If you want cheap or great mpg and don't care about looks-Honda's are always good, old econo-boxes like ford festiva, aspire, geo metro... Ugly but effective and super cheap.