The Roof Cleaning Institute Of America Training & Certification Forum
"Find A Certified Roof Cleaner Directory"

Remember that it is both a liquid and a gas so even if you are almost empty, there is still gas emitting from the chemicals that can and will cause metal to rust so adequate ventilation is a must.

I have seen where people have mounted hose reels to the ceilings so they hang down, I have seen hose reels mounted onto barn style doors, I have seen them stacked up 3 and 4 high before so just about anything is possible.

You could mount them to the ceiling hanging down so you still have the floor space and you can put one in front of the other, just hang some bright colored rags from them so nobody bumps their head on them. Rolling up the hose would not be that big of a deal, instead of on the floor, you are reaching up to roll up the hose.

Over on PWI and TGS there are pictures of trailer rigs and a few guys mounted hose reels up high so they take up less room on the trailer.