I have read multiple posters use squeeze bottles to decorate with. The only squeeze bottles I can find in my area are the ones made for ketchup and mustard that already have the hole cut. Would those work or is the hole too big? Do you find bottles where you can cut your own opening?
These are my favorite:
I've found the smaller size is easier to use and hold and you can change the tip size easily.
My local cake shop had them in stock once upon a time, but I had to order them from the above link after that.