I wanted to sell my old broken iPhone but was reluctant because of the data stored on it. I couldn't reset it because it wouldn't power on. So the buyer said I could just reset it via the utility so it would reset itself once it went online. I did that but now the guy (who repaired it) says I would need to enter my password corresponding to my Apple ID one more time in order for him to use the phone after the reset. Is it true or is he trying to scam me?
It is a feature called activation lock Click for more info I would suggest changing your Apple ID password to something simple then after about 5 minutes change it back
The answer depend on how you use your iPhone. In this case, you said "reset it via the utility so it would reset itself once it went online. I did that" do you mention about erase data option on iCloud webpage? If yes then the answer is YES, the phone do require your password to pass Activation Lock.