The minimum extension of the more common Hasselblad bellows units is 63.5 mm exactly. It ends at 202 mm.

There is no question, really bellows or tubes.
The bellows is used to get extension you cannot get with tubes.
Yes, you can stack tubes. But it's not recommended to stack more than two. Three maximum. (every extra limk between amera and lens introduces extra play.) And unless your tubes are all long, stacking them will not get you what the bellows will deliver.

So use a bellows when you need the extension it offers. Else stick with tubes.

How much exposure compensation is needed depends on lens and extension, so is different for combinations of different lenses with the same tubes.
The Calculator on Hasselblad Historical will produce all the numbers you want. Just put the length of the tube in the "total extension" box if you want to get the figures with the lens set to the infinity mark, in the "extra extension" box if you want to get the figures for when you also use the lens' full extension.