Grizz 700 Stuck Valve-rings? Smoking

Hey guys,
I have a line on a 07 grizzly 700 for a pretty good price. Owner says it may have a stuck valve or need new rings. He says it smokes a little while driving. Only 2100 miles on it. in great shape. Thought I would be a good one to fix. I am not sure how much this is going to cost to fix or be a problem. I am handy but have not done a valve/ring job before. He was told that it may have a "sticky valve and/or may need rings" Going to look at it today.

i would probably pull the engine If i need to and bring it to someone to repair/rebuild.

Any advice on this subject.

Thanks
Joe