With the dip in his back and the low belly I would say at least 4 but its a complete swag. But he is a nice buck and one anyone would be proud to take I think. Good luck.
From that angle too difficult to guess....he isn't a yearling but doubt he is older than 9. More pics...without I'd say 2-7years old haha!
He looks like a 3.5 to me. Doesn't really have the body yet to be a 4.5 but every area is different so tough to be for sure. Definitely a shooter to me.