These are both marvelous albums, I purchased both of them relatively early upon release, the Purple Rain buy was a 33 (vinyl). I actually think I also bought a cassette version of Purple Rain, before buying the CD some years later. The record was either lost, worked over, or otherwise out of commission.
We wore out Appetite while playing Nintendo. One slightly older friend was into metal big time, so he was all over Guns N Roses. I recall "Mr. Brownstone" being my favorite track the first few times hearing the album. I kind of got off of it though once And Justice for All came out the summer of '88.