Just wondering

I often get asked to demo chimney's that exceed 25' and are often located in trickey (unlevel PA) places. How could I go about figuring the most cost effective way to make the correct choice to hire a scaff company to set up and break down, or buy my own and deal with all that headache. I know there are many factors but the older the I get, the more willing I am to spring the extra xyz because I do these jobs alone.

I've done these jobs the basic way, off a ladder, semi perm roof jacks blah blah blah. I see my friends over in EU with some cool setups, and whilst not always viable, I can adapt to what I think I might learn here.