You can sand any imperfections in the base, but it would probably be a good idea to recoat that area with base (especially if it's a metallic or pearl type color)
As far as buffing by hand, this is not suggested. Though you can do it, it would take forever to get it as good as a variable speed buffer could do it.
I would suggest getting a good Dewault or Makita variable speed buffer. Both tend to run around $210 or so.
If you want to reduce the texture, you'll need to also wetsand it before buffing. If it's a slight texture, 2000 grit should do the trick.
As far as buffing by hand, this is not suggested. Though you can do it, it would take forever to get it as good as a variable speed buffer could do it.
I would suggest getting a good Dewault or Makita variable speed buffer. Both tend to run around $210 or so.
If you want to reduce the texture, you'll need to also wetsand it before buffing. If it's a slight texture, 2000 grit should do the trick.