On average your guests will have 1 drink per person per hour. If you are only having these liquor, and not beer & wine as well, we would suggest getting more vodka and rum than the other liquors. Each 60oz bottle will give you approx 60 drinks. So estimating that your event is 5 hours. we would suggest getting approx. 3-4 bottles of vodka, 3-4 bottles of rum and 2-3 of the other liquors. Remember that you can always return any unopened bottles to the LCBO