I made my low lying fog machine using a large igloo cooler on wheels, I fabbed up a stainless steel lowering cage, I put a stainless steel stand off on the bottom(if the dry ice touches the plastic bottom it may crack it), I am using a modified livestock heater on a temp controller, 2- 6" high volume whisper quiet industrial fans, and 4" plastic flex duct that feeds into a dispersing head(it looks like a real wide vacuum head) to spread the fog evenly.
The heater and fans are switched indepentantly.
I pay $5 a pound for the ice. 2 lbs will do a great job for about 5 minutes. Long enough for the first dance.
I opted for the cooler because it helps dampen the boiling sound of the ice.
I spent around $150, but unless you have a mig welder and good knowledge of electrical circuits I wouldn't try it.