To delete a Proposal Type, from the main menu, arrive at the Proposal Types setup with this path: Setup > Proposals > Proposal Types.
The Proposal Types list will be displayed. Locate the record you want to delete, and then click on the Delete button.
A confirmation message will be displayed. If the Proposal Type has never been used on a Proposal, the record will be deleted. If the Proposal Type has been used on a Proposal, the record will be marked as inactive. Click on the Yes button to confirm the deletion/inactivation of the record.