I’m bidding on a number of one story office complexes similar to this.
I’m using a Wash-iT Pro. Portable, but nice to leave in one location.
Assuming you have enough hose to reach to all of the buildings, would you drag hose from building to building if there are customers (cars) present, or would you move your pure water system from building to building, etc.
The only thing I don’t like about the wash-it or any other system is breaking it down , if you have a bunch of moves or just need it for a small job. You could check into a small tank and pump . I got one from harbor freight for 75 bucks with a coupon, The pump is ok for short term, but I figure the 15 gallon tank was worth that alone. Or WCR has a great pump which I just got and used for the first time. I had 250 ft of hose out and it ran like a champ. I can be set up and running in 2 minutes or move it between buildings real quick. Big jobs that need more water than I carry , I set the wash-it in the middle. 2 - 7 gallon jugs , use one while filling the other. I know it’s a little added expense, but I bet I use the WFP at least twice as much as I used to with the ease of using a pump.
I’m not as good at conserving the water as some guys, but today I did 40- 45 divided light windows with the 15 gallon tank with adding 7 more gallons. I’ve only had to take tank out of truck one time and that was where you couldn’t drive near buildings. for that I have a folding dolly, it’s a real hump for the dolly, not to mention me getting it out of truck. Now I would just use the pump I got from WCR, and put 7 gallons on dolly. Very rarely 250 ft of hose doesn’t get it. Forgot to mention, marine battery works better than using you vehicle
I’d probably move it 3 or 4 times but use the hose to get between buildings where it makes sense. If you’re going to be crossing entryways then use a wet floor sign to straddle the hose so people don’t trip.
It might be time to use the profits from the job to upgrade your setup :-D. I have my filters mounted on my truck, can run 150’ of 3/4" to the spigot, feed the system, and then pull out 300’ of 1/4" to clean the windows - this usually lets me wrap around a house if I wanted. I usually go to one side and then wrap around the back from the other side to get the remaining 3/4 of the house.
I feel I need to put my disclaimer on this: it’s not really recommended, and will probably shorten the life of the battery. That said, ours has been going strong for 2+ years without issue. If it dies tomorrow (somewhat short of the expected lifespan for those batteries) I’ll be more than happy to replace it with another one. For me, the convenience and space savings is well worth the possible trade-off in longevity. Plus it’s really not a good idea to have a lead acid battery inside the cabin because of the gases given off.