You don't need to Exit Qatar at all, You Just Need an NOC from Your Sponsor, Rest leave it to the Company PRO.

2) If you need to apply for Family Visit Visa, you need to have NOC from your Company, Bank Statement ( For Me to Sponsor my Brother, Didn't Required Bank Statement ), Salary Certificate, But 1st you need to Obtain your RP.

3) Make Sure to Clarify with your Company if they are Giving you Family Status Visa or Not, and Minimum Salary to Sponsor your Wife and Kids on Visit Visa is 7000 QAR Basic, and to Apply for their Resident Permit Basic Salary should be 10,000 QAR.

4) For Pakistani's Visa is a Bit of a Problem, But not that much as The Company i work in Hire Pakistanis Every Second Day without any Hassle of Visa....