If you get a Paterson tank that holds 3 rolls of 35mm you can use it to process two rolls of 120. You could also get one of the Mod 54 inserts that would let you process up to 6 sheets of 4x5 in the same tank. Alternatively get the smaller Paterson tank that is made for 2 rolls of 35mm and you can do one roll of 120 in this. you can process one sheet of 4x5 by curving it around the inner wall of the tank, emulsion side in. I've done this many times with no problems. Your choice depends on how much film you use.