This Old House had a segment on scaffolding some years back,
and they mentioned several types. One that could be suitable
for painting was a system that had an aluminum "plank" that
mounted to uprights, possibly made from 2x4s nailed together to
make a "4x4" (probably 3.0" x 3.5"). the plank was raised with
foot jacks. It was ideally suited for two people, though one
person could handle it if he/she didn't mind running back and
forth a little. The uprights were set on the ground (some
kind of foundation would be needed), while the top frames
were lagged to the house.
I've never had the pleasure :-) of painting a two story house,
but even for a single story one, scaffolding can turn a nasty
job into one relatively simple. Of course, the scaffolding for
a single story house can look a lot like a few saw horses and
a couple of planks, but you get the idea.
Pete Brooks
When it was first painted, the painter used a "2 * 2x4 => 4x4 lagged to
the roofline" as supports for a makeshift scaffold. Didn't look like
fun to me, but he'd obviously done it before.
Gary