restrict user search access based on created user

I have 2 questions

1. We have a scenario  where certain users can create users in the FIM portal. When user logs into the portal. He should be able to search only users created by him. What kind of MPR is required for this case.
2. Also if i have 2 MPR's where 1 MPR grants permission and 2nd MPR denys permission for same user. Is there a precendence like which MPR will win??

Raj-Shpt