Blasting is a horrible job and you really need to know your
s**t grit and whatever you're blasting onto or removing very well otherwise you can get into deep trouble pretty easily.
I got a quote of £3k and another of £6k to blast my house, both + VAT. A third bloke didn't sound like he knew what he was doing so he was out of the running.
The cheaper one did it off a ladder, the second one wanted scaff putting up (as an extra) so you can see there is a vast difference in prices.
The more expensive one looked and spoke like Taggart

he was a proper miserable old git and very much 'You will do it my way, I know best, end of conversation'.
As you can imagine I chose the first team, they did it in 3 days with 2 tons of specialist grit between two of them. They worked non-stop for 8 - 9hrs per day and really earned their money, I gave them a generous tip when they'd done. They were happy to tidy up the main of the grit and leave it here as it's not worth their while to take it and dump it at the recyclers.
Mine was hassle free as there is no-one around me to upset with the dust and noise so bear that in mind.
I used to know one guy who had his own van mounted cherry picker which gave him an advantage in many situations.
I know a fair bit more on the topic, but i've typed enough irrelevant info for now!