Have enough time for room decoration.

When renting the room, keep in mind delivery and placement of your centerpieces and other decorations takes time. Also, this is the most unpredictable time for all vendors. Each one needs time to unload, bring everything in the room, fix or produce and then place. Yes, it can be done quickly, but what if building looses power for 15 minutes? In the last few years we had two parties we have decorated extensively with just one hour between previous party in the room and my client's party. Very entertaining...

If you can avoid – do it! Rent the room for more hours, ask the facility manager if your vendors can come to a nearby room earlier. 9 times out of 10 they will help.