I'm asking you. Are you certain the property is yours to sell? If it is, by all means, do with your property what you will.
It seems to be you are uncertain if you're still trying to get in contact with your friend.
As a military spouse who's left guns behind while we went out of the country, I am very familiar with leaving guns behind for extended periods of time. I am familiar with not being able to ship firearms with me in my every move because of laws and living situations.
Are you certain this property is now yours? If so, sell it. You don't need to contact your friend.
It comes to mind you may be asking about the legality of selling a pistol he owned. I can't speak for VA law but in TX, guns can be passed around (gifted or sold to same state residents), no paperwork necessary.
I was answering thinking that you were uncertain if your buddy would be mad if he found out later you sold his gun that he now wants to take back.