Is This Job Offer Genuine? How to Verify Before Accepting a Chief Accountant Role

One South African-based gentleman has sent me a letter of offer for the post of Chief Accountant (salary to be paid in Indian Rupees) without giving the company's name, stating that the factory is under construction, and requesting me to join at the earliest. If I accept the offer, they are ready to send a VISA as well.

How to Verify the Offer's Authenticity

How can I know whether this offer is genuine or fake? What precautions should be taken in this regard? How can I confirm its authenticity? Should I go ahead with the offer as the salary offered is Rs. 90,000 per month? Please guide me, sir, in your reply to my mail.

Thanks.

First of all, where are you located? Your nametag above says you are in Chicago, USA.

Clarification on Interviews and Communication

Coming to your query, please clarify, have you attended any interviews for this job? Was there any kind of communication regarding this earlier between both of you?

Regards,
TS

Sir, I am located in Ongole near Vijayawada (AP). I have not attended any interview for this job after submitting my resume and passport details. They told me that an interview is not necessary as I am an experienced person (aged 57). There has been email communication between us. They have requested me to join at the earliest. As per a telephonic discussion, they may send a VISA if I convey my consent for the same. I have asked them to wait for some time. Please examine the matter and advise on the precautions I may take before joining there for duties. Your valuable guidance in this regard would be appreciated.

Thank you.