I know several professional welders, many who have done it for quite a long time, and some are the old timers as well....all of them except 2 use auto helmets, though all of them have also spent alot of money on thier helmets, so no junk...the 2 welders I know who do not use an auto helmet (father and son) have a very good reason...they are iron workers, and are normally working several stories up...spend alot of money on a good helmet, drop it once, and its trash...buy an elcheapo helmet, drop it and it breaks, who cares?
they both have decent auto helmets for use at home...
alot of things (clamps and jigs) that you will need/want you will figure out as you go, and alot of those types of things you just build as you need them...one thing you may want to build before getting into any other projects, after the welding cart anyway, is a welding table...just a small basic table, at a height comfortable to either sit or stand at while working (your choice) made of all steel, usually with a heavy mesh or screen top...you can clamp pieces through the screen top, or around the sides of the table, or just set your pieces on it, leave the ground clamp on the leg of the table, and start welding
arrow magnets are nice to have as well...also at least one angle finder, clamps and visegrips, aluminum speedy square, clamps and visegrips, steel protracter is nice to have, and you should also get some clamps and visegrips, you'll use them alot, and you never seem to have enough