Welcome to the site - there are a lot of good people here willing to help.
I've tried virtually every rust stripping method and firmly believe that plain old brown sand in the hands of a capable person is the best option. Acid dipping is too messy and leaves many parts exposed that you will not be able to effectively recoat unless you pay really big bucks and have the car e-coated following stripping. Walnut shells and plastic media will strip paint, but not do a very good job on rust and are extraordinarily expensive if you can find someone to do it. Bead blasting is more for soft metals or surfaces where you want a satin finish. I bead blasted many parts in preparation for plating, but for painting more a more aggressive surface texture is a plus. Brown sand is relatively cheap, breaks down easily (not too agressive) and will do great at removing rust. It's the pressure, not heat, that warps metal (imagine thousands of tiny ball peen hammers). I've sand blasted many sheet metal parts with absolutely no damage, but it just takes a few minutes to destroy a hood or quarter if someone doesn't know what they're doing or doesn't turn down the pressure. To that point, it's nearly impossible to damage anything with a siphon feed blaster because the pressure is so low. If you were to do this yourself, you could buy a $50 blaster and have at it.
Anything more aggressive than brown sand should not be used except on very durable parts like the frame, rear end, suspension parts, etc...
The only method I can't comment on is soda blasting. The soda breaks down ultra fast (it cannot be reused even once) but is inexpensive and because it breaks down so fast, it is not as agressive as sand.
