Update - I completed this warehouse job yesterday. I took the advice from the veterans on here, and the job went smooth. We used a bucket truck to seal/tape off anything electrical that would pose a problem, and to clean the rafters/ceiling. We had no problems or safety issues during the cleaning.
The job took longer than I wanted because of water flow problems. We couldn't run two units because the water supply wasn't sufficient enough. Lesson learned. Next time I will be prepared with a water tank on my trailer. Not a big problem overall, but made for a longer day/night than expected.
The customer (national beverage company) was very pleased with the work and is scheduling to have another larger warehouse cleaned. We also discussed a maintenance plan and will be working out the specifics soon. Does anyone have any advice on frequency of service, length of contract or other specifics for a warehouse cleaning maintenance contract?
Also on a side note, while talking to the warehouse manager, he divulged some specifics about the other bids he received. He received a bid from a company in WV that using some type of vacuum system to clean. They gave a quote for only cleaning the ceiling for $15k. The ceiling is 9800 sf.