How to hit four or five stories?

Send out some bids for 3 to 5 story Apartment complexes, But all I have is a four gallon per min machine, and a 12 volt, seven gallon, a minute softwash. I can do 3 stories, no problem. But any advice would help or what you recommend to get that high? Thanks.

With my AR45 running 12 GPM using 300 feet of 5/8" hose I can get about 40’ with no wind. Aside from renting a lift you could rig up a waterfed pole with a softwash tip attachment but honestly those are really hard to handle after even 20’.