So you're doing a DIY wedding and you're supplying the booze (better get a caravan bar to serve it!)
You don't want to run out but you also don't want to spend too much and end up with loads of leftovers, there are some online calculators you can use to help figure out how much to buy, but I think they based their quantities off a mormon community research group and allocate like 4 drinks per person for the whole event. I'm guessing your guests don't fall within this category so you'll need a little more than they say, you definitely don't want to run out remember! Your caravan bar (cause you've definitely booked one right?) will be able to give you a better guide on quantities.
So now that you've bought a bunch of alcohol, there are a few things you can do to make sure you're not wasting a drop.
1. Don't give out cans of soft drink
You can save atleast half of your soft drink supply by not handing out cans. Guests never finish them, they'll drink half, put it down and walk away. And now you've got mess to clean up (because they definitely don't put them in the bin!)
2. Do Hire a cool room
You've spent a few of grand on alcohol and you're planning on just putting everything in some eskies with ice to save the $250 on a cool room. It sounds great in theory but realistically it's not worth the hassle. Every client who's attempted this only end up with enough eskies and ice for half of the drinks. So the other half of your drinks will be sitting in the heat, the ice has melted by this point so there's no chance of them cooling down. If you managed to get ALL your drinks in eskies either you've broken up all the cartons or they're sitting soggy from the melted ice, so now you can't return ANYTHING. Dan Murphys happily refund any unused, unopened cartons with a receipt, so if you've overbought you don't need to stress, you were smart and ordered a cool room so all your cartons are perfectly intact and you can return absolutely everything that wasn't touched, which could end up getting you a nice $1000+ refund!
3. Don't put bottles of wine on all the tables
60% of the wedding will be drinking beer, and while some guests would love a bottle of wine in front of them during dinner to help themselves it's not doing any favours for your budget when it comes to returning any unused alcohol. Say you have 100 guests, a caterer will generally pop a bottle of white, red and bubbly in front of every 6 guests, That's 16 bottles of white, 16 bottles of red and 16 bottles of champagne that are now opened, one or two glasses poured out of each and you can't return a single bottle. Instead of putting bottles on the tables for guests to open have your bar staff roam with one bottle of each to top up guests glasses, that way you only have one bottle opened at a time and no wastage!
4. Do Finish your bar service a little earlier than the reception finishes
Most people want drinks available up until the very end of the night, and that's a fair call, but it's not necessary... The dance floor is winding down, some guests have already left, the bus is due to pick everyone up and by this point people don't give two shits about what they're drinking, they're just drinking for the sake of it. So save some cash, finish drinks service a little earlier, give everyone a water and let them dance the edge off and wake up a little fresher!
I hope these tips have helped, there are plenty of ways to save money without missing out on any of the things you love!