from experience the travel time and getting the machinery is the most expensive, i pay about $140 for the machine, and $70 each way for the delivery, that's already $280 without a guy to install it for me (i do it myself, as I agree it is expensive to outsource this work, especially if you're a small operation) i'd be over the moon if i could get someone to do this for me at that price! I understand why they charge a lot though, of course someones gotta risk going up there, imagine if the machine failed forcing you into the ground to become a quadriplegic, the risk is there, we sometimes become oblivious to it, but a bit of bad luck and 1 job could be your last. Most of the people have let it rip into you, and rightly so i guess, Firstly you just need to quote properly so the costs are not your problem but your clients, you might want to invest in a couple of lift machines and rent them out, (perhaps a second business?) since you said they seem to be impossible to find?. The idea of the Scaffold system isn't bad either, if you have the time/muscle to put it together i own a mini scaffold which has already paid for itself on the first job i used it on.