Hay Steve, good to see you back! As for paint, I have no good advice except to say that spray paints have gotten a lot better in the last ten years. You’ll probably get good results with whatever you try…
The color will probably be a bigger indicator of success. Paint it her favorite color, and you’ll be the best grandpa ever. My daughter is into Lime Green these days. Seems that’s a hip color among the young ladies. I’m just say’en find out what she likes, and paint it that color 8)