Taking seed investment from an unknown friend

Hello, myself sameer ahmed khan. Me & my business partner came up with a startup idea to organise a part of retail industry and the idea is a boom. We have started getting traction already and then met a guy who is a mutual friend, he was showing interest in our idea from the first day and asked equal stake for ₹30l, but we rejected. We had 0 knowledge about stake etc, so we contacted one of our mentor. He asked to only spend 8-10% for 10%. The mutual friend of ours, say that his dad is an investment banker & he too studied investment banking and they own a company in canada and they invests money in lot of firms, also they invest foreign investments from other firms or investors and earn a comission out of it. He shares a lot of marketing strategies with us, he shows that he has a vast knowledge about everything about business and stuff. He says he is the same kind of visionary about the idea as we founders are. He accepted for 10%, but as our mentor asked to go for a background check of that person before going for a deal. Please advice us, what to do. We hardly know this guy since 2 weeks, he just shared stories & tragedies about their family only. Even my bestfriend, who introduced me to him, when asked he too doesn't know about his background at all. We have a meeting today afternoon with him to finalize and clear few doubts. Shall we proceed with the deal? Or is it really important to know the person, his life, where is he getting the investment from? And if he is a genuine guy? Please advice.