I ring a local firm. $250 and done.

for about an hour to an hour and a halfs work thats a pretty hefty hourly rate.

Jase2985:

 

for about an hour to an hour and a halfs work thats a pretty hefty hourly rate.

 

Usually takes them a day.

I use selleys sugar soap and soft broom - does wonders

Hmmmm ... thanks people

A second vote for the extendable brush with built-in soap dispenser - works a treat and can reach to the top of our tallest external wall (which is damn high for a one-story house).

I'm sure ours is a Raven, which also sells packs of the soap in cylinder-shaped blocks. Only issue is we need to be careful with ours is the bottom 'corners' (the ones which don't have the window wiper blade thing along it), as a good wack with them can scratch paint.  

I have a water blaster but wanted to avoid using it for obvious reasons .... likewise the additional effort of using a brush on a pole

I'll check out the soap dispensing brushes though.

But arent these good comments of little value unless we know the exterior?

Painted weatherboard.

Stucco

Cellcrete

Fibrous paneks

Concrete

Concrete block

Brick

All these have various levels of ability to tolerate water blaster, chemicals, plus soap cleaning ability.

Sorry ... painted (about 10 years ago now) weatherboards.  Corner section and across the road from a large hill & reserve (Tinakori Hill).  Most is in good condition but a couple of strips of "green" on road sides.

I've always used bleach mixed 1:1 with water in a garden sprayer. to kill any moss and mold. then water blast being careful not to blast water in windows.

For what its worth, I'm a tradesman Painter and Decorator.