Hey all, not sure if this is the place to post this but it seems somewhat relevant. Also I already made this post under a friend's account by accident and she asked me to remove it and deleted her account. 
Anyway, we live in Ontario, Canada and are looking at a gorgeous garden venue in
 Newcastle, ON. They have an approved caterer that we must use, and she 
is lovely and well known in the area. However, neither the venue nor the
 caterer provide the alcohol that we need
 for our bar.
The venue does, however, provide us with certified bartenders, all 
glassware, and any mixes and condiments that we need. The bartenders and
 glassware are included in the rental fee, and they charge for the mixes
 and condiments based on consumption. They say
 that typically ranges between $3-$5 per person depending on your 
group's usage.
This all seems reasonable to me, however I am wary about having to 
provide our own alcohol. I have been looking at calculators online but 
I'm still not able to grasp how much I should expect to spend.
Our wedding will be about 90 guests which will include some light 
drinkers but mostly people who really drink. We will be serving booze 
for 6 hours (1 of which is cocktail hour) and it will be an open bar.
Anyway, to make a long story longer, I just want to know if providing 
one's own alcohol is a common thing? Does it save money or end up 
costing just as much/ more than when the venue or caterer provides it? 
Finally, how do you know how much to buy? The worst
 possible thing that could happen would be to run out of booze!
Thanks!!
                
                
