It may or may not be a problem. Don’t let it scare you away until you know there’s some reason to be. It could be perfectly legit with no problems. Or, it could have problems.
What should I say to the dealer?
“Say, the CarFax says this vehicle has been sitting on the lot since last year....why?”
“What has been done to maintain the vehicle?”
If I want to buy this vehicle, should I require that they do full oil service and check/replace other fluids?