Im not a big fan of sandblasting a car due to the mess. You will have a nasty sandstorm and sand will be all over your driveway/grass/house/car. Everything will get covered. If you do do it, I suggest a full face mask (like a welding helmet), dust mask, hat, earplugs, long sleeve shirt. You get the idea.
I would look into soda blasting. You can usually rent the machine for around $200 and the media you will use will cost about $40. The stuff just needs to be washed off and neutralized (use vinegar) and you have a nice clean car. Not to expensive.