I had my Abbot, which is both steel and aluminium, blasted and sprayed by K Blasting from Brixham (who I thoroughly recommend by the way, as they have MVs of their own). It's very messy and I wouldn't suggest doing it to a complete vehicle where the interior is already finished. No matter how well you mask and cover, an amazing amount of grit will still get in. I took a deliberate decision to blast and paint the exterior before starting on the interior as that way the grit that gets inside isn't really an issue. For reference, it took them about four hours to blast the Abbot.
For smaller components off the vehicle I use a "Machine Mart" type blasting gun on a compressor, but there's no way it could do the job a proper blasting setup can. You've only got to look at the difference in size of compressor and hose!
Andy