We hired a snow machine off Halogen DJ's a few days ago. Not only did it work very well for us but the staff there were very understanding as well.
A few days before the hire, we had to postpone to another date and then change it up again because of unforeseen circumstances. They walked us through the whole process and communicated with us rather than the other way around.
I will definitely be using them again.

Approximate cost: $80