Copy selected documents from one document library to another programmatically in ms crm 2011

Hi,

My requirement is as mentioned below in ms crm 2011.

I need to copy the selected entity(Opportunity) documents to another entity(Quote) documents folder in ms crm 2011 programmatically.

In crm 2011 we are using the Opportunity and Quote entities relationship. We need to give the option to the user to select the  Opportunity entity attached documents and once submit need to copy these documents and move to the Quote documents library folder.

I am retrieving the Opportunity entity attached documents and showing up in custom apsx page with check boxes.  

Now if I select the specific Opp documents in this custom page using check boxes and click on Submit, I need to copy these selected documents and move to the Opp related Quote documents folder.

How can I achieve this using c# code. Please let me know if anybody already worked on this activity before.

Thanks,

Yadav