is the 7 series reliable

Hello seamles1, To answer your question, it depends how well the car has been maintained thusfar. I would look for a Certified BMW, and purchase an after market warranty, if you are looking at a higher mileage car. The original warranty is 4 year / 50,000 miles, and BMW does that for two reasons. Maintenance is expensive and this strategy pushes those whom can afford it, into a new one. I would look at a Carfax report on any car that you maybe serious about, and if possible have it checked out by a BMW dealer, they will be happy to tell you everything that the car may need, from air cleaner to rear suspension bushings and everything in between. Relatively inexpensive compared to your $25,000.00 + investment. They are certainly beautiful cars, and the 750Li is as comfortable as you can get for 4 large adults. Good luck on your search... Rats