Visit your local library, find a copy of Consumer Reports Used Car Guide and see what it has to say about its plusses and minuses, based on the opinions of owners of the same car. That’s where to start.
I know next to nothing about them, Infinity is a pretty uncommon brand on the road in these parts, but as a luxury vehicle it probably has a lot of bells and whistles, automatic this, automatic that, and those kinds of functions often have more reliability problems as they age than the basic stuff like the body integrity & drivetrain. It’s also the case that you frequently have to repair that stuff when it breaks b/c there’s no effective work-a-round available. Given all that, I’d be disinclined to purchase an older luxury vehicle myself. But if you have the resources to fix the stuff as it breaks, not overly concerned about the car being off the road during the repair process, could make for a nice ride. And much more reasonably priced that a new one.