Preparation for painting pebble dash?

What's the best preparation for painting these walls. I assume these are pebble dash walls??

I'm not going to paint them myself, the gable end is far too high but would spraying be better than brush & roller?

I'm supplying the paint myself, but what questions should i be asking when i get people around to quote? Many thanks for reading it

Don't get it painted.

It will get dirty, and need doing every few years.

It's a job for life.

Sprayed mine , 4hrs for front , flank and rear, still good after 10 years.