I've had 3 pickups including a Toyota Hilux Intimidator (Japanese import) and it was the muts nuts. Seriously good. I wasn't window cleaning at the time though. It all depends on your circumstances. If you really can't be bothered to run two vehicles and you can make your own water, and have a really compact round, then I would go for it. You could always come home and refill.
I have to buy my water, 30 mins there and back. I am upsizing from a 350 litre ford connect to whatever I can use to hold 650, but that is my personal preference. It really does depend on how you work, whether you make your own water, what extra services you provide (so more gear in the van) etc, etc. If you're just house bashing, and it's all local, then the best vehicle I've ever owned (and i'm 52 and owned lots) is the Toyota Hilux.
PS They are a bit bouncy with an empty load.