Ask him to give you proof of ownership of the car, and valid guarantee / surety that his friend will be definitely there at the time of transfer of ownership.
Last year, I intended to buy a Honda Civic 8th gen. Karachi registered. It seemed neat and clean and offer also seemed reasonable, however, seller was showing lots of "Taizi".
He could not satisfy me regarding any proof of ownership, and then when I said that since you do not have any proof of ownership and car is also not registered in your name, so I'll not transfer the amount in your's account, rather the person's who owns it, and you can settle with him.
2ndly, he'll have to fully support me regarding transfer of ownership.
He got extremely infuriated / offended and his tone also changed immediately. He said:
"!... بھا ئی آپکو گا ری آپ کے نام پے چاہیے نا ، یہ میری ذمہ داری ہے ! میں آپکو کروا دوں گا آپ پریشان نا ہوں..."
I politely winded up and dropped the call.
Thanks to ALLAH ALMIGHTY that He Saved me from scam / loss.