Security for housewarming party

[robertsm]

We are looking for the event security guards for the housewarming party. My sister has bought a new condo from Toronto condo market last day. We are hosting a party at night for 500 people. I have seen most of the people hire security guards or have other security options installed in these kinds of events. Is it good to hire event security professionals to ensure that all the guests are safe? We want to enjoy our party to the fullest without any worries. Does anyone know any professional where I could find security professional for the upcoming housewarming party? We expect the following services:
Guest list monitoring
Parking lot security
Monitor the residence and surroundings
What are the other things that should be considered before hiring a guard for these kinds of events? Any suggestions are welcome. Please let me know your thoughts. Thanks in advance !!!