I strongly suggest you get a 7 series with the Certified Series Warranty. Parts on the 7 Series are not cheap. If the car has over 100k make sure you have all the records of what has been done. I had to replace my temperature sensor $800 then the rad $400 on my 7 series before it got to 110k. I was lucky that it was covered under the Certified series.
Buy Badride's car it is worth the money plus he has the Certified Series Warranty.