Anyone know the general difference in weights between aluminum and fiberglass truck caps?

I'm finding I am going to spend about $1000 on a FG cap. I had no idea they were so expensive.

 

lookj around used their all over here. my fiber glass one weighs a ton. 2 guys strain with it but can do it. (long bed)

 

I have a 8' aluminum one with the sliding windows. Its light enough for me to get it off an on myself, just slide it to me, and put it over my head then on saw horses. Last time I tried it with a glass shell I almost busted my neck

 

I think my Leer weighs 180-200 lbs.

 

My raised roof FG one (long bed) made by Guidon that I just sold was 365#. A heavy *****! Sold it for $450 and it was not in the best shape cosmetically, but nothing broken either. New ones around here are about 1K +/- also.

 

I had a Leer 8' fiberglass with longer side windows and full glass rear door. It was HEAVY but managable for two big guys. The one I have now is about 5-600#'s with the cabover and full galvanized roof rack with expanded metal floor. www.callencamper.com

 

I bought a used Gazelle Crown over the weekend. It's not new but looks in solid shape and the exterior is in good shape. heck... $300 is better than $1000! And no tax!!
I was able to lift the side of it myself. I am hoping that two of us can do it.