Hi Aftab,

Here is link that describes full procedure of upgrading to Odoo 9 with related costs. https://xpansa.com/odoo/how-to-do-odoo-upgrade/

Short answer is that it is possible only with signing Enterprise Contract with Odoo now.

This not currently possible through OCAUpgrade, see the last comment here https://github.com/OCA/OpenUpgrade/issues/400

Hi,

The official way to migrate form odoo8 to odoo9, is to contact odoo company, they will charge for this service. Here is  Link.
Here is the documentation on how to do that by yourself : Link.

Hope this helps.