You have posted:
-"how much leagal expese I need to carry on an aproximate like Lawer fee etc."
No. This you have to settle with your lawyer. You may contact an experienced and competent service lawyer at your location. Your near and dear ones can guide you to the competent lawyer. If you wish to contact LCI lawyer you may click at “Related Labor & Service Law Lawyers" mentioned on the bottom of this web page.
-"I contacted my ex company [Datamatics] VP-HR." "I would take legal action against Datamatics for holding my Gratuity and Experience letter but he was not bother with this at all."
Employee should record such situations (audio/visual), pushing and dumping the employee in crowded courts than resolving the matter with the good offices of the employer. VP-HR is a senior and good office of the company. HO-HR is another good office.
-"I possess all the evidences require like my resignation letter, Overseas Deputation Policy, My email communication with Management and HR regional and Head Office." Let your lawyer examine all the record and inputs given by you and then you may look into the merits and decide upon the appropriate remedy/forum which may be O/o Controlling authority for gratuity, O/o labor commissioner, civil court etc.
You may also seek the counsel of elders in the family, competent and experienced well wishers.
Prepare a list of all phone calls (with bills) emails letters etc and demand expenses incurred by you on these and include cyber café, internet, parking traveling charges etc.
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