I got it. I was able to copy and paste elements from one revit file to another. The only way I found that it worked was by
1. selecting desired objects in file 1
2. press CTRL+C to copy to clipboard
3. in the menu bar, go to VIEW and switch windows to view file 2
4. press CTRL+P to paste to file 2 where they need to go
5. Sing Hallelujah! Yes!
I was so excited when this actually worked. I had made a deck with furniture, office furniture, and more. I really, really didn't want to redraw them. It seemed to me that clicking COPY from the menu bar and PASTE in the file 2 did not copy the elements I chose to the file. So, try the above directions and, hopefully, you'll have the same success as I did.
Thanks,
Amy