Thanks mate some good advice thereJust thought I would add my thoughts as I have converted several rounds to wfp.
First expect to loss a few customers some just can't get over there own bias that it can't work.
Iv had people cancel becuase it leaves the walls wet. (What about rain???)
As has been mentioned before offer a comeback service. Avoids most problems.
Second it will take forever to convert your round.
Personaly one tip I have found works is to scrub everything clean then love on to next house. Then come back and clean them again. You can check the windows when u come back before you re clean them. I find this faster and more confident boosting that u have done a good job.
Third I work with a second person.
We used to use a lot of water, but now we use about 600l a day. But we have 800l capacity, but never fill it.
We have just over 1250kg payload. We only ever went as high as 750l when filling for weight reasons.
At first you will be very very slow. I would say depending on the house maybe even 4x slower.
You will also use a stupid about of water.
Even on your second clean you will have to take longer.
But as you get used to the system you will speed up.
As for speed comparison it's a no brainer.
My other friend is still trad. He can do about 2.5 semis an hour in our local area. (No frames just cills.)
I can do 5 easy including moving van etc.
The more compact the work the fast wfp is.
Lastly I would go down having a 1000l tank at home with ro system. We have a 55l per minute pump. If we did ever need water we can get over 500l in 10 mins.