Alarm bells should be ringing at these 2 points
Point 1) if he is a Barrister, why is his email address domain hotmail.com as opposed to a Nigerian Law Company name
Point 2) Western Union Money Transfer, with no bank references nor company quote codes for insurance policies, etc.
All very suspicious

Attn: Sir.

With the approval of the Management of Nigeria Agip Oil Company, we are delighted to formally offer you the Appointment to work with Nigeria Agip Oil Company for the provision of Expatriates Relation Services for the period duly specified in your Offer Letter. Please find attached Copy of your Appointment Letter for your perusal and immediate action if the terms of work is acceptable to you. Upon thorough review and acceptance of this Appointment Package, dot your signature in the space indicated in the last page of the Offer Letter and return same back to us via email attachment within a period of 7 working days.


Once you accept and sign this offer, you are to contact the immigration lawyer with the below email address and request for information required to enable him process your str visa.Please note that your consistency is highly needed to enable him do his job and get you str visa on time, also enadavour to keep us posted as regards your progress with the lawyer

IMPORTANT INFORMATION

Visa Information:

The below email and phone number belongs to the immigration lawyer who will be charge of your STR visa, once you agree to the terms and condition of this offer by signing your signature on the space provided, you are to immediately contact the below email address and phone number and let the lawyer know that you have accepted the job request str visa requirements from him.

OZOR CHAMBERS.
ADDRESS: 47 WOGU ROAD,
P.O. BOX 937
PORT HARCOURT
TEL: +2348186023473
E-mail: [email protected]
Designation: Solicitor and Advocate in Law
Contact Person: Barrister Ugonna Ozor.

Upon receipt of the required documents from your side the immigration lawyer will secure your residence and work permit here in Nigeria and will contact the Nigerian Consulate in your country and fax all your documents to them to facilitate your visa.

Within a space of 7 working days after your papers have been faxed to the consulate, we shall notify you on when to go to the Consulate Office in your country for the endorsement of your international passport, brief interview and issuance of visa.


Thanks,

Rick White.