I’m trying to figure out of these Picasso sketches are real and worth money. Let me know if you know how to check.

I’ve also managed to score a few Normal Rockwell prints, and one Van Gogh, although of all the prints I seriously doubt the Van Gogh is real. It just looks too flat and clear. The Picassos are obviously real sketches, but the question is was he the one who sketched them are are they reprints. The Rockwells are clearly panted, but, again, by him, or by someone else?