This video goes over how to set up a mesh/character so that you can use it either as an Arms model, or for 1st/3rd person by utilizing the FPS Mesh Tool. For UFPS, we need to have 3 materials (arms, head, body). It is very difficult to export models in order to break up the materials, and it takes some time/skill. Using this tool, you can do it very quickly.
UFPS
https://www.assetstore.unity3d.com/en...
FPS Mesh Tool
https://www.assetstore.unity3d.com/en...
Speedball Player
https://www.assetstore.unity3d.com/en...
Soldier Pack
https://www.assetstore.unity3d.com/en...
Latest Game
My latest game - http://bit.ly/1xVc7ja