For a typical 10-player T1-base tournament set (using 10/8/10/2 = 500 stacks):
100x 1
80x 5
100x 25 (+ 4x for T1 color-ups)
20x 100 (+ 4x for T5 color-ups)
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308 chips are all that's needed, bare minimum.
For a 400-chip set, (using 15/12/9/2 = T500 tournament stacks):
150x 1
120x 5
100x 25
30x 100
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400 chips, which also includes the extra chips needed to color-up the 1s and 5s during tourney play.
To add to that 400-chip set so that it could also be used for a 1/2 cash game, you would want to add 200 more $5 chips.
Or, to instead also use it for a 25c/50c cash game, add 100x 25c chips, 50x $1 chips, and 50x $5 chips.
If you are playing micro-stakes cash games (like 5c/10c), you are probably better off changing the tournament set to a T.25-base (vs the T1-base set I listed) and adding 100 nickels and 100 quarters.