Let me just say, I never walk into an airport now when the name "Mohamed Atta" does not come to mind. To pack liquids for 3 people, I use Ziploc bags and lots of them.
To pack the liquid stuff-- suntan lotion, shaving cream, toothpaste, moisturizer etc in our luggage...I used gallon size Ziploc bags.
For suntan lotion, I had the plastic grocery bag the suntan lotion came in when I purchased it. Took the bag, lotion bottles and all, rolled it up, placed into Ziploc and then squeezed out as much of the air as I could (saves room and prevents the bag from bursting).
Much of the other stuff I tried to group together. Example-- nail polish, top coat, nail polish remover. Put all in one bag, squeezed out air and rolled.
THEN when finished I took all my Ziploc bags and put them together inside a zippered heavy plastic zippered case I had saved from the last time I purchased a sheet set. Voila, worked great! Nothing leaked on the way down and on the way back a couple of little things leaked slightly, but only 'cause Jerry had packed those and didn't make sure the cap was secured.