When you're looking at used cars to buy it's not unusual for the used car of 8 to 10 years old to have 100,000 miles or more on the car.
The average distance and miles driven per year is between 12,000 to 15,000 miles so a car with 100,000 to 150,000 miles is not bad for an older car.
At 100,000 to 150,000 miles the car is just broken in and usually has another 100,000 miles or more to go so I would buy a car that had 150,000 miles on it as long as it had a good price.
So if the car is 10 years old and has 150,000 miles you should expect another 10 years out of the car as long as it's been maintained and you keep it maintained properly.
Make sure the belts are changed, oil is changed, transmission fluid is changed etc and the car should last you a long time.
If the car has 300,000 miles on it or more then I would say that is high mileage but even then the cars can still be really reliable at that high of mileage.