Reduce poligons and fix errors on a 3D character

I have a 3D character that I bought on turbosquid. I have hired an artist that made some modifications to it but unfortunately the modifications are not yet completed. The current character is in FBX format.

I need someone to:
1. Fix the errors that the character has at the hair (hair must be double faced and it is not, some errors at the material)
2. Fix the errors at the eyes - again some error at the materials
3. Reduce the poligon no on the newly added objects
4. Export to Unity

Later on skinning has to be added to the character.

Budget can be discussed.

Happy bidding!!!