My experience with blasting:
EQUIPMENT: I bought a Clark 90 pound syphon feed blaster from Tractor Supply and it's paid for itself many times over. I'm sure it doesn't cut as quickly as a professional setup but I'm VERY pleased with the way it works and can see no reason to buy a pressurized blaster. It's never clogged and I've done everything from doors to bolts with no warping or other problems. When I blasted my replacement doors they were heavily pitted and there was absolutely no warping despite some pretty aggressive blasting on my part. Syphon blasters also require much less volume of air to operate making it ideal for the casual user.
Other benefits of a syphon blaster include not having to wear special protective clothing. I wear a respirator, light leather gloves, jeans and a t-shirt along with a full hood which I bought at Tractor Supply. I bought a cheap sheet of clear plastic glazing (Home Depot) and make my own lenses for the hood. You can also clear any blockage by simply holding your finger over the nozzle and pulling the trigger. This back-flushes the feed tube.
I also have a HF Tabletop blaster that, once modified, works very well for small parts but finding an efficient way of keeping the dust down inside the thing (without spending a lot of money) has proven to be an issue.
COMPRESSOR: I have a 60 gallon Kobalt unit I bought from Lowes. This is the absolute minimum for blasting. I run my blaster at 80 psi and the compressor is probably running 60% of the time. I also try to take it easy as not to overwork the compressor.
ABRASIVES: I started using Sakrete Builders Sand (Home Depot) sifted through a home made sifter made from aluminum window screen. This worked very well and was cheap. I now use Black Diamond from Tractor Supply, slightly more expensive but you don't have to sift it and it cuts faster. It's all I use now. Always sift recycled abrasive.
WARPING: There are two schools of thought on why sandblasting warps body panels.
One theory is heat buildup, which doesn't sound very logical when you consider that along with the abrasive you are also blasting the area with large volumes of air which you would think would be cooling the surface.
The other theory is that each grain of abrasive is hammering the surface causing it not only to stretch but also work harden. Although I've no proof that either is the culprit I tend to agree with the second theory.
WORKSPACE: If you have a shady place large enough to lay out a 20 x 20 tarp that will work just fine. The tarp makes it very easy to recycle your abrasive. I do all my blasting in the carport using a tarp to keep the abrasive off the siding and to speed abrasive recycling.
BLASTING A CAB: I doubt I'll be blasting the inside of my cab. It's almost impossible to clean out the abrasive from all the hidden areas inside the cab and I've heard too many horror stories of the abrasive blowing out onto fresh paint. I'll wirebrush loose surface rust and treat with Eastwood's Rust Converter.
That's my experience, YMMV
