Anyway, in answer to your question - no used car's aren't a money pit, unless you get one which is
Me personally, I'm only ever buying via private sales in the future, or from main dealers. Getting a car from a small trader these days is asking for trouble for the following reasons:
A) They get all their cars from the auctions which are normally trade ins. A lot of people make the decision to get rid of their cars and buy a new one when several things are wrong with their car and they can't be bothered/afford to fix it. They don't want to sell it privately because people generally have a conscious and they don't want to lumber the next person with it (or they are just cognisant that the buyer knows their phone number/where they live!) - so they trade it in because it is then the problem of the trader. Unfortunately a lot of cars have hidden problems which you need to spend some time with the car to identify, which traders obviously don't have time to do - but which the next owner will find out in a week or two and have the hassle of trying to fix.
B) You pay a premium to buy from a trader as there seems to be this perceived protection you get and the warranty they sell you sounds wonderful when you buy the car, but when you come to use it in 3 months time - it's a bag of ****.
C) I've always found private sellers to be great - I've been able to meet the person selling the car so have an idea as to it's been looked after and used, you get to keep all the invoices and history (which traders have to shred these days!) and you get a better price.