You can have 1 tank for 120 and 35mm, either a plastic tank with adjustable reels or a stainless tank with 2 or 3 sets of reels will do.
As for chemicals, you need 1 or 2 developers, 1 fixer, lots of water.
You can choose long life developers, such as Rodinal or HC110 for cheapness.
Or you can prepare the 5l of Xtol/D76 and "break it"into small bottles filled to the brim.
Now for each ISo do you mean puching or different films?
HC110 can be used for almost any film, google covington Hc110 and you'll have a super resource.
Rodinal works best for ISo 100 and down but if you do not mind grain 400 and faster can be done painlessly.
Originally posted by Gooshin this will be primarily for B&W at the moment.
i dont mind doing bulk so as to not waste chemicals
my only concern though is ISO selection, do i have to use different chemicals for different ISO's?
is there a crash course on developing out on the net that someone could recomend.
i have processed film before... but i was 9 years old, hehehe.