Hey so I've been reading a lot about what I should be looking for when buying an 8 and today I was looking at one and when I was looking under the car I notice that the back right tire had significantly less tread than the other tires, is this just an older tire or could this be a problem with the car? sorry if this has been answered somewhere else thanks for reading this and helping me out!

 

That's not really something the internet can answer, the seller will have to tell you that.

+ 100 points for paying attention to tread wear though.

 

It's not recommended to drive a vehicle for too long with uneven tread. If you need to purchase new tires, buy 2 and keep the other (the GOOD tire currently on the car) as a spare.
Also, where is the wear? It could implicate an issue with the suspension.